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rocksdb/db/db_iterator_test.cc
Peter Dillinger 9d0cae7104 Eliminate unnecessary (slow) block cache Ref()ing in MultiGet (#9899) 
Summary:
When MultiGet() determines that multiple query keys can be
served by examining the same data block in block cache (one Lookup()),
each PinnableSlice referring to data in that data block needs to hold
on to the block in cache so that they can be released at arbitrary
times by the API user. Historically this is accomplished with extra
calls to Ref() on the Handle from Lookup(), with each PinnableSlice
cleanup calling Release() on the Handle, but this creates extra
contention on the block cache for the extra Ref()s and Release()es,
especially because they hit the same cache shard repeatedly.

In the case of merge operands (possibly more cases?), the problem was
compounded by doing an extra Ref()+eventual Release() for each merge
operand for a key reusing a block (which could be the same key!), rather
than one Ref() per key. (Note: the non-shared case with `biter` was
already one per key.)

This change optimizes MultiGet not to rely on these extra, contentious
Ref()+Release() calls by instead, in the shared block case, wrapping
the cache Release() cleanup in a refcounted object referenced by the
PinnableSlices, such that after the last wrapped reference is released,
the cache entry is Release()ed. Relaxed atomic refcounts should be
much faster than mutex-guarded Ref() and Release(), and much less prone
to a performance cliff when MultiGet() does a lot of block sharing.

Note that I did not use std::shared_ptr, because that would require an
extra indirection object (shared_ptr itself new/delete) in order to
associate a ref increment/decrement with a Cleanable cleanup entry. (If
I assumed it was the size of two pointers, I could do some hackery to
make it work without the extra indirection, but that's too fragile.)

Some details:
* Fixed (removed) extra block cache tracing entries in cases of cache
entry reuse in MultiGet, but it's likely that in some other cases traces
are missing (XXX comment inserted)
* Moved existing implementations for cleanable.h from iterator.cc to
new cleanable.cc
* Improved API comments on Cleanable
* Added a public SharedCleanablePtr class to cleanable.h in case others
could benefit from the same pattern (potentially many Cleanables and/or
smart pointers referencing a shared Cleanable)
* Add a typedef for MultiGetContext::Mask
* Some variable renaming for clarity

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9899

Test Plan:
Added unit tests for SharedCleanablePtr.

Greatly enhanced ability of existing tests to detect cache use-after-free.
* Release PinnableSlices from MultiGet as they are read rather than in
bulk (in db_test_util wrapper).
* In ASAN build, default to using a trivially small LRUCache for block_cache
so that entries are immediately erased when unreferenced. (Updated two
tests that depend on caching.) New ASAN testsuite running time seems
OK to me.

If I introduce a bug into my implementation where we skip the shared
cleanups on block reuse, ASAN detects the bug in
`db_basic_test *MultiGet*`. If I remove either of the above testing
enhancements, the bug is not detected.

Consider for follow-up work: manipulate or randomize ordering of
PinnableSlice use and release from MultiGet db_test_util wrapper. But in
typical cases, natural ordering gives pretty good functional coverage.

Performance test:
In the extreme (but possible) case of MultiGetting the same or adjacent keys
in a batch, throughput can improve by an order of magnitude.
`./db_bench -benchmarks=multireadrandom -db=/dev/shm/testdb -readonly -num=5 -duration=10 -threads=20 -multiread_batched -batch_size=200`
Before ops/sec, num=5: 1,384,394
Before ops/sec, num=500: 6,423,720
After ops/sec, num=500: 10,658,794
After ops/sec, num=5: 16,027,257

Also note that previously, with high parallelism, having query keys
concentrated in a single block was worse than spreading them out a bit. Now
concentrated in a single block is faster than spread out, which is hopefully
consistent with natural expectation.

Random query performance: with num=1000000, over 999 x 10s runs running before & after simultaneously (each -threads=12):
Before: multireadrandom [AVG    999 runs] : 1088699 (± 7344) ops/sec;  120.4 (± 0.8 ) MB/sec
After: multireadrandom [AVG    999 runs] : 1090402 (± 7230) ops/sec;  120.6 (± 0.8 ) MB/sec
Possibly better, possibly in the noise.

Reviewed By: anand1976

Differential Revision: D35907003

Pulled By: pdillinger

fbshipit-source-id: bbd244d703649a8ca12d476f2d03853ed9d1a17e
2022-04-26 21:59:24 -07:00

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// Copyright (c) 2011-present, Facebook, Inc. All rights reserved.
// This source code is licensed under both the GPLv2 (found in the
// COPYING file in the root directory) and Apache 2.0 License
// (found in the LICENSE.Apache file in the root directory).
//
// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file. See the AUTHORS file for names of contributors.
#include <functional>
#include "db/arena_wrapped_db_iter.h"
#include "db/db_iter.h"
#include "db/db_test_util.h"
#include "port/port.h"
#include "port/stack_trace.h"
#include "rocksdb/iostats_context.h"
#include "rocksdb/perf_context.h"
#include "table/block_based/flush_block_policy.h"
#include "util/random.h"
#include "utilities/merge_operators/string_append/stringappend2.h"
namespace ROCKSDB_NAMESPACE {
// A dumb ReadCallback which saying every key is committed.
class DummyReadCallback : public ReadCallback {
public:
DummyReadCallback() : ReadCallback(kMaxSequenceNumber) {}
bool IsVisibleFullCheck(SequenceNumber /*seq*/) override { return true; }
void SetSnapshot(SequenceNumber seq) { max_visible_seq_ = seq; }
};
// Test param:
// bool: whether to pass read_callback to NewIterator().
class DBIteratorTest : public DBTestBase,
public testing::WithParamInterface<bool> {
public:
DBIteratorTest() : DBTestBase("db_iterator_test", /*env_do_fsync=*/true) {}
Iterator* NewIterator(const ReadOptions& read_options,
ColumnFamilyHandle* column_family = nullptr) {
if (column_family == nullptr) {
column_family = db_->DefaultColumnFamily();
}
auto* cfd =
static_cast_with_check<ColumnFamilyHandleImpl>(column_family)->cfd();
SequenceNumber seq = read_options.snapshot != nullptr
? read_options.snapshot->GetSequenceNumber()
: db_->GetLatestSequenceNumber();
bool use_read_callback = GetParam();
DummyReadCallback* read_callback = nullptr;
if (use_read_callback) {
read_callback = new DummyReadCallback();
read_callback->SetSnapshot(seq);
InstrumentedMutexLock lock(&mutex_);
read_callbacks_.push_back(
std::unique_ptr<DummyReadCallback>(read_callback));
}
return dbfull()->NewIteratorImpl(read_options, cfd, seq, read_callback);
}
private:
InstrumentedMutex mutex_;
std::vector<std::unique_ptr<DummyReadCallback>> read_callbacks_;
};
TEST_P(DBIteratorTest, IteratorProperty) {
// The test needs to be changed if kPersistedTier is supported in iterator.
Options options = CurrentOptions();
CreateAndReopenWithCF({"pikachu"}, options);
ASSERT_OK(Put(1, "1", "2"));
ASSERT_OK(Delete(1, "2"));
ReadOptions ropt;
ropt.pin_data = false;
{
std::unique_ptr<Iterator> iter(NewIterator(ropt, handles_[1]));
iter->SeekToFirst();
std::string prop_value;
ASSERT_NOK(iter->GetProperty("non_existing.value", &prop_value));
ASSERT_OK(iter->GetProperty("rocksdb.iterator.is-key-pinned", &prop_value));
ASSERT_EQ("0", prop_value);
ASSERT_OK(iter->GetProperty("rocksdb.iterator.internal-key", &prop_value));
ASSERT_EQ("1", prop_value);
iter->Next();
ASSERT_OK(iter->GetProperty("rocksdb.iterator.is-key-pinned", &prop_value));
ASSERT_EQ("Iterator is not valid.", prop_value);
// Get internal key at which the iteration stopped (tombstone in this case).
ASSERT_OK(iter->GetProperty("rocksdb.iterator.internal-key", &prop_value));
ASSERT_EQ("2", prop_value);
}
Close();
}
TEST_P(DBIteratorTest, PersistedTierOnIterator) {
// The test needs to be changed if kPersistedTier is supported in iterator.
Options options = CurrentOptions();
CreateAndReopenWithCF({"pikachu"}, options);
ReadOptions ropt;
ropt.read_tier = kPersistedTier;
auto* iter = db_->NewIterator(ropt, handles_[1]);
ASSERT_TRUE(iter->status().IsNotSupported());
delete iter;
std::vector<Iterator*> iters;
ASSERT_TRUE(db_->NewIterators(ropt, {handles_[1]}, &iters).IsNotSupported());
Close();
}
TEST_P(DBIteratorTest, NonBlockingIteration) {
do {
ReadOptions non_blocking_opts, regular_opts;
anon::OptionsOverride options_override;
options_override.full_block_cache = true;
Options options = CurrentOptions(options_override);
options.statistics = ROCKSDB_NAMESPACE::CreateDBStatistics();
non_blocking_opts.read_tier = kBlockCacheTier;
CreateAndReopenWithCF({"pikachu"}, options);
// write one kv to the database.
ASSERT_OK(Put(1, "a", "b"));
// scan using non-blocking iterator. We should find it because
// it is in memtable.
Iterator* iter = NewIterator(non_blocking_opts, handles_[1]);
int count = 0;
for (iter->SeekToFirst(); iter->Valid(); iter->Next()) {
ASSERT_OK(iter->status());
count++;
}
ASSERT_EQ(count, 1);
delete iter;
// flush memtable to storage. Now, the key should not be in the
// memtable neither in the block cache.
ASSERT_OK(Flush(1));
// verify that a non-blocking iterator does not find any
// kvs. Neither does it do any IOs to storage.
uint64_t numopen = TestGetTickerCount(options, NO_FILE_OPENS);
uint64_t cache_added = TestGetTickerCount(options, BLOCK_CACHE_ADD);
iter = NewIterator(non_blocking_opts, handles_[1]);
count = 0;
for (iter->SeekToFirst(); iter->Valid(); iter->Next()) {
count++;
}
ASSERT_EQ(count, 0);
ASSERT_TRUE(iter->status().IsIncomplete());
ASSERT_EQ(numopen, TestGetTickerCount(options, NO_FILE_OPENS));
ASSERT_EQ(cache_added, TestGetTickerCount(options, BLOCK_CACHE_ADD));
delete iter;
// read in the specified block via a regular get
ASSERT_EQ(Get(1, "a"), "b");
// verify that we can find it via a non-blocking scan
numopen = TestGetTickerCount(options, NO_FILE_OPENS);
cache_added = TestGetTickerCount(options, BLOCK_CACHE_ADD);
iter = NewIterator(non_blocking_opts, handles_[1]);
count = 0;
for (iter->SeekToFirst(); iter->Valid(); iter->Next()) {
ASSERT_OK(iter->status());
count++;
}
ASSERT_EQ(count, 1);
ASSERT_EQ(numopen, TestGetTickerCount(options, NO_FILE_OPENS));
ASSERT_EQ(cache_added, TestGetTickerCount(options, BLOCK_CACHE_ADD));
delete iter;
// This test verifies block cache behaviors, which is not used by plain
// table format.
} while (ChangeOptions(kSkipPlainTable | kSkipNoSeekToLast | kSkipMmapReads));
}
TEST_P(DBIteratorTest, IterSeekBeforePrev) {
ASSERT_OK(Put("a", "b"));
ASSERT_OK(Put("c", "d"));
EXPECT_OK(dbfull()->Flush(FlushOptions()));
ASSERT_OK(Put("0", "f"));
ASSERT_OK(Put("1", "h"));
EXPECT_OK(dbfull()->Flush(FlushOptions()));
ASSERT_OK(Put("2", "j"));
auto iter = NewIterator(ReadOptions());
iter->Seek(Slice("c"));
iter->Prev();
iter->Seek(Slice("a"));
iter->Prev();
delete iter;
}
TEST_P(DBIteratorTest, IterReseekNewUpperBound) {
Random rnd(301);
Options options = CurrentOptions();
BlockBasedTableOptions table_options;
table_options.block_size = 1024;
table_options.block_size_deviation = 50;
options.table_factory.reset(NewBlockBasedTableFactory(table_options));
options.compression = kNoCompression;
Reopen(options);
ASSERT_OK(Put("a", rnd.RandomString(400)));
ASSERT_OK(Put("aabb", rnd.RandomString(400)));
ASSERT_OK(Put("aaef", rnd.RandomString(400)));
ASSERT_OK(Put("b", rnd.RandomString(400)));
EXPECT_OK(dbfull()->Flush(FlushOptions()));
ReadOptions opts;
Slice ub = Slice("aa");
opts.iterate_upper_bound = &ub;
auto iter = NewIterator(opts);
iter->Seek(Slice("a"));
ub = Slice("b");
iter->Seek(Slice("aabc"));
ASSERT_TRUE(iter->Valid());
ASSERT_EQ(iter->key().ToString(), "aaef");
delete iter;
}
TEST_P(DBIteratorTest, IterSeekForPrevBeforeNext) {
ASSERT_OK(Put("a", "b"));
ASSERT_OK(Put("c", "d"));
EXPECT_OK(dbfull()->Flush(FlushOptions()));
ASSERT_OK(Put("0", "f"));
ASSERT_OK(Put("1", "h"));
EXPECT_OK(dbfull()->Flush(FlushOptions()));
ASSERT_OK(Put("2", "j"));
auto iter = NewIterator(ReadOptions());
iter->SeekForPrev(Slice("0"));
iter->Next();
iter->SeekForPrev(Slice("1"));
iter->Next();
delete iter;
}
namespace {
std::string MakeLongKey(size_t length, char c) {
return std::string(length, c);
}
} // namespace
TEST_P(DBIteratorTest, IterLongKeys) {
ASSERT_OK(Put(MakeLongKey(20, 0), "0"));
ASSERT_OK(Put(MakeLongKey(32, 2), "2"));
ASSERT_OK(Put("a", "b"));
EXPECT_OK(dbfull()->Flush(FlushOptions()));
ASSERT_OK(Put(MakeLongKey(50, 1), "1"));
ASSERT_OK(Put(MakeLongKey(127, 3), "3"));
ASSERT_OK(Put(MakeLongKey(64, 4), "4"));
auto iter = NewIterator(ReadOptions());
// Create a key that needs to be skipped for Seq too new
iter->Seek(MakeLongKey(20, 0));
ASSERT_EQ(IterStatus(iter), MakeLongKey(20, 0) + "->0");
iter->Next();
ASSERT_EQ(IterStatus(iter), MakeLongKey(50, 1) + "->1");
iter->Next();
ASSERT_EQ(IterStatus(iter), MakeLongKey(32, 2) + "->2");
iter->Next();
ASSERT_EQ(IterStatus(iter), MakeLongKey(127, 3) + "->3");
iter->Next();
ASSERT_EQ(IterStatus(iter), MakeLongKey(64, 4) + "->4");
iter->SeekForPrev(MakeLongKey(127, 3));
ASSERT_EQ(IterStatus(iter), MakeLongKey(127, 3) + "->3");
iter->Prev();
ASSERT_EQ(IterStatus(iter), MakeLongKey(32, 2) + "->2");
iter->Prev();
ASSERT_EQ(IterStatus(iter), MakeLongKey(50, 1) + "->1");
delete iter;
iter = NewIterator(ReadOptions());
iter->Seek(MakeLongKey(50, 1));
ASSERT_EQ(IterStatus(iter), MakeLongKey(50, 1) + "->1");
iter->Next();
ASSERT_EQ(IterStatus(iter), MakeLongKey(32, 2) + "->2");
iter->Next();
ASSERT_EQ(IterStatus(iter), MakeLongKey(127, 3) + "->3");
delete iter;
}
TEST_P(DBIteratorTest, IterNextWithNewerSeq) {
ASSERT_OK(Put("0", "0"));
EXPECT_OK(dbfull()->Flush(FlushOptions()));
ASSERT_OK(Put("a", "b"));
ASSERT_OK(Put("c", "d"));
ASSERT_OK(Put("d", "e"));
auto iter = NewIterator(ReadOptions());
// Create a key that needs to be skipped for Seq too new
for (uint64_t i = 0; i < last_options_.max_sequential_skip_in_iterations + 1;
i++) {
ASSERT_OK(Put("b", "f"));
}
iter->Seek(Slice("a"));
ASSERT_EQ(IterStatus(iter), "a->b");
iter->Next();
ASSERT_EQ(IterStatus(iter), "c->d");
iter->SeekForPrev(Slice("b"));
ASSERT_EQ(IterStatus(iter), "a->b");
iter->Next();
ASSERT_EQ(IterStatus(iter), "c->d");
delete iter;
}
TEST_P(DBIteratorTest, IterPrevWithNewerSeq) {
ASSERT_OK(Put("0", "0"));
EXPECT_OK(dbfull()->Flush(FlushOptions()));
ASSERT_OK(Put("a", "b"));
ASSERT_OK(Put("c", "d"));
ASSERT_OK(Put("d", "e"));
auto iter = NewIterator(ReadOptions());
// Create a key that needs to be skipped for Seq too new
for (uint64_t i = 0; i < last_options_.max_sequential_skip_in_iterations + 1;
i++) {
ASSERT_OK(Put("b", "f"));
}
iter->Seek(Slice("d"));
ASSERT_EQ(IterStatus(iter), "d->e");
iter->Prev();
ASSERT_EQ(IterStatus(iter), "c->d");
iter->Prev();
ASSERT_EQ(IterStatus(iter), "a->b");
iter->Prev();
iter->SeekForPrev(Slice("d"));
ASSERT_EQ(IterStatus(iter), "d->e");
iter->Prev();
ASSERT_EQ(IterStatus(iter), "c->d");
iter->Prev();
ASSERT_EQ(IterStatus(iter), "a->b");
iter->Prev();
delete iter;
}
TEST_P(DBIteratorTest, IterPrevWithNewerSeq2) {
ASSERT_OK(Put("0", "0"));
EXPECT_OK(dbfull()->Flush(FlushOptions()));
ASSERT_OK(Put("a", "b"));
ASSERT_OK(Put("c", "d"));
ASSERT_OK(Put("e", "f"));
auto iter = NewIterator(ReadOptions());
auto iter2 = NewIterator(ReadOptions());
iter->Seek(Slice("c"));
iter2->SeekForPrev(Slice("d"));
ASSERT_EQ(IterStatus(iter), "c->d");
ASSERT_EQ(IterStatus(iter2), "c->d");
// Create a key that needs to be skipped for Seq too new
for (uint64_t i = 0; i < last_options_.max_sequential_skip_in_iterations + 1;
i++) {
ASSERT_OK(Put("b", "f"));
}
iter->Prev();
ASSERT_EQ(IterStatus(iter), "a->b");
iter->Prev();
iter2->Prev();
ASSERT_EQ(IterStatus(iter2), "a->b");
iter2->Prev();
delete iter;
delete iter2;
}
TEST_P(DBIteratorTest, IterEmpty) {
do {
CreateAndReopenWithCF({"pikachu"}, CurrentOptions());
Iterator* iter = NewIterator(ReadOptions(), handles_[1]);
iter->SeekToFirst();
ASSERT_EQ(IterStatus(iter), "(invalid)");
iter->SeekToLast();
ASSERT_EQ(IterStatus(iter), "(invalid)");
iter->Seek("foo");
ASSERT_EQ(IterStatus(iter), "(invalid)");
iter->SeekForPrev("foo");
ASSERT_EQ(IterStatus(iter), "(invalid)");
ASSERT_OK(iter->status());
delete iter;
} while (ChangeCompactOptions());
}
TEST_P(DBIteratorTest, IterSingle) {
do {
CreateAndReopenWithCF({"pikachu"}, CurrentOptions());
ASSERT_OK(Put(1, "a", "va"));
Iterator* iter = NewIterator(ReadOptions(), handles_[1]);
iter->SeekToFirst();
ASSERT_EQ(IterStatus(iter), "a->va");
iter->Next();
ASSERT_EQ(IterStatus(iter), "(invalid)");
iter->SeekToFirst();
ASSERT_EQ(IterStatus(iter), "a->va");
iter->Prev();
ASSERT_EQ(IterStatus(iter), "(invalid)");
iter->SeekToLast();
ASSERT_EQ(IterStatus(iter), "a->va");
iter->Next();
ASSERT_EQ(IterStatus(iter), "(invalid)");
iter->SeekToLast();
ASSERT_EQ(IterStatus(iter), "a->va");
iter->Prev();
ASSERT_EQ(IterStatus(iter), "(invalid)");
iter->Seek("");
ASSERT_EQ(IterStatus(iter), "a->va");
iter->Next();
ASSERT_EQ(IterStatus(iter), "(invalid)");
iter->SeekForPrev("");
ASSERT_EQ(IterStatus(iter), "(invalid)");
iter->Seek("a");
ASSERT_EQ(IterStatus(iter), "a->va");
iter->Next();
ASSERT_EQ(IterStatus(iter), "(invalid)");
iter->SeekForPrev("a");
ASSERT_EQ(IterStatus(iter), "a->va");
iter->Prev();
ASSERT_EQ(IterStatus(iter), "(invalid)");
iter->Seek("b");
ASSERT_EQ(IterStatus(iter), "(invalid)");
iter->SeekForPrev("b");
ASSERT_EQ(IterStatus(iter), "a->va");
iter->Prev();
ASSERT_EQ(IterStatus(iter), "(invalid)");
delete iter;
} while (ChangeCompactOptions());
}
TEST_P(DBIteratorTest, IterMulti) {
do {
CreateAndReopenWithCF({"pikachu"}, CurrentOptions());
ASSERT_OK(Put(1, "a", "va"));
ASSERT_OK(Put(1, "b", "vb"));
ASSERT_OK(Put(1, "c", "vc"));
Iterator* iter = NewIterator(ReadOptions(), handles_[1]);
iter->SeekToFirst();
ASSERT_EQ(IterStatus(iter), "a->va");
iter->Next();
ASSERT_EQ(IterStatus(iter), "b->vb");
iter->Next();
ASSERT_EQ(IterStatus(iter), "c->vc");
iter->Next();
ASSERT_EQ(IterStatus(iter), "(invalid)");
iter->SeekToFirst();
ASSERT_EQ(IterStatus(iter), "a->va");
iter->Prev();
ASSERT_EQ(IterStatus(iter), "(invalid)");
iter->SeekToLast();
ASSERT_EQ(IterStatus(iter), "c->vc");
iter->Prev();
ASSERT_EQ(IterStatus(iter), "b->vb");
iter->Prev();
ASSERT_EQ(IterStatus(iter), "a->va");
iter->Prev();
ASSERT_EQ(IterStatus(iter), "(invalid)");
iter->SeekToLast();
ASSERT_EQ(IterStatus(iter), "c->vc");
iter->Next();
ASSERT_EQ(IterStatus(iter), "(invalid)");
iter->Seek("");
ASSERT_EQ(IterStatus(iter), "a->va");
iter->Seek("a");
ASSERT_EQ(IterStatus(iter), "a->va");
iter->Seek("ax");
ASSERT_EQ(IterStatus(iter), "b->vb");
iter->SeekForPrev("d");
ASSERT_EQ(IterStatus(iter), "c->vc");
iter->SeekForPrev("c");
ASSERT_EQ(IterStatus(iter), "c->vc");
iter->SeekForPrev("bx");
ASSERT_EQ(IterStatus(iter), "b->vb");
iter->Seek("b");
ASSERT_EQ(IterStatus(iter), "b->vb");
iter->Seek("z");
ASSERT_EQ(IterStatus(iter), "(invalid)");
iter->SeekForPrev("b");
ASSERT_EQ(IterStatus(iter), "b->vb");
iter->SeekForPrev("");
ASSERT_EQ(IterStatus(iter), "(invalid)");
// Switch from reverse to forward
iter->SeekToLast();
iter->Prev();
iter->Prev();
iter->Next();
ASSERT_EQ(IterStatus(iter), "b->vb");
// Switch from forward to reverse
iter->SeekToFirst();
iter->Next();
iter->Next();
iter->Prev();
ASSERT_EQ(IterStatus(iter), "b->vb");
// Make sure iter stays at snapshot
ASSERT_OK(Put(1, "a", "va2"));
ASSERT_OK(Put(1, "a2", "va3"));
ASSERT_OK(Put(1, "b", "vb2"));
ASSERT_OK(Put(1, "c", "vc2"));
ASSERT_OK(Delete(1, "b"));
iter->SeekToFirst();
ASSERT_EQ(IterStatus(iter), "a->va");
iter->Next();
ASSERT_EQ(IterStatus(iter), "b->vb");
iter->Next();
ASSERT_EQ(IterStatus(iter), "c->vc");
iter->Next();
ASSERT_EQ(IterStatus(iter), "(invalid)");
iter->SeekToLast();
ASSERT_EQ(IterStatus(iter), "c->vc");
iter->Prev();
ASSERT_EQ(IterStatus(iter), "b->vb");
iter->Prev();
ASSERT_EQ(IterStatus(iter), "a->va");
iter->Prev();
ASSERT_EQ(IterStatus(iter), "(invalid)");
delete iter;
} while (ChangeCompactOptions());
}
// Check that we can skip over a run of user keys
// by using reseek rather than sequential scan
TEST_P(DBIteratorTest, IterReseek) {
anon::OptionsOverride options_override;
options_override.skip_policy = kSkipNoSnapshot;
Options options = CurrentOptions(options_override);
options.max_sequential_skip_in_iterations = 3;
options.create_if_missing = true;
options.statistics = ROCKSDB_NAMESPACE::CreateDBStatistics();
DestroyAndReopen(options);
CreateAndReopenWithCF({"pikachu"}, options);
// insert three keys with same userkey and verify that
// reseek is not invoked. For each of these test cases,
// verify that we can find the next key "b".
ASSERT_OK(Put(1, "a", "zero"));
ASSERT_OK(Put(1, "a", "one"));
ASSERT_OK(Put(1, "a", "two"));
ASSERT_OK(Put(1, "b", "bone"));
Iterator* iter = NewIterator(ReadOptions(), handles_[1]);
iter->SeekToFirst();
ASSERT_EQ(TestGetTickerCount(options, NUMBER_OF_RESEEKS_IN_ITERATION), 0);
ASSERT_EQ(IterStatus(iter), "a->two");
iter->Next();
ASSERT_EQ(TestGetTickerCount(options, NUMBER_OF_RESEEKS_IN_ITERATION), 0);
ASSERT_EQ(IterStatus(iter), "b->bone");
delete iter;
// insert a total of three keys with same userkey and verify
// that reseek is still not invoked.
ASSERT_OK(Put(1, "a", "three"));
iter = NewIterator(ReadOptions(), handles_[1]);
iter->SeekToFirst();
ASSERT_EQ(IterStatus(iter), "a->three");
iter->Next();
ASSERT_EQ(TestGetTickerCount(options, NUMBER_OF_RESEEKS_IN_ITERATION), 0);
ASSERT_EQ(IterStatus(iter), "b->bone");
delete iter;
// insert a total of four keys with same userkey and verify
// that reseek is invoked.
ASSERT_OK(Put(1, "a", "four"));
iter = NewIterator(ReadOptions(), handles_[1]);
iter->SeekToFirst();
ASSERT_EQ(IterStatus(iter), "a->four");
ASSERT_EQ(TestGetTickerCount(options, NUMBER_OF_RESEEKS_IN_ITERATION), 0);
iter->Next();
ASSERT_EQ(TestGetTickerCount(options, NUMBER_OF_RESEEKS_IN_ITERATION), 1);
ASSERT_EQ(IterStatus(iter), "b->bone");
delete iter;
// Testing reverse iterator
// At this point, we have three versions of "a" and one version of "b".
// The reseek statistics is already at 1.
int num_reseeks = static_cast<int>(
TestGetTickerCount(options, NUMBER_OF_RESEEKS_IN_ITERATION));
// Insert another version of b and assert that reseek is not invoked
ASSERT_OK(Put(1, "b", "btwo"));
iter = NewIterator(ReadOptions(), handles_[1]);
iter->SeekToLast();
ASSERT_EQ(IterStatus(iter), "b->btwo");
ASSERT_EQ(TestGetTickerCount(options, NUMBER_OF_RESEEKS_IN_ITERATION),
num_reseeks);
iter->Prev();
ASSERT_EQ(TestGetTickerCount(options, NUMBER_OF_RESEEKS_IN_ITERATION),
num_reseeks + 1);
ASSERT_EQ(IterStatus(iter), "a->four");
delete iter;
// insert two more versions of b. This makes a total of 4 versions
// of b and 4 versions of a.
ASSERT_OK(Put(1, "b", "bthree"));
ASSERT_OK(Put(1, "b", "bfour"));
iter = NewIterator(ReadOptions(), handles_[1]);
iter->SeekToLast();
ASSERT_EQ(IterStatus(iter), "b->bfour");
ASSERT_EQ(TestGetTickerCount(options, NUMBER_OF_RESEEKS_IN_ITERATION),
num_reseeks + 2);
iter->Prev();
// the previous Prev call should have invoked reseek
ASSERT_EQ(TestGetTickerCount(options, NUMBER_OF_RESEEKS_IN_ITERATION),
num_reseeks + 3);
ASSERT_EQ(IterStatus(iter), "a->four");
delete iter;
}
TEST_F(DBIteratorTest, ReseekUponDirectionChange) {
Options options = GetDefaultOptions();
options.create_if_missing = true;
options.prefix_extractor.reset(NewFixedPrefixTransform(1));
options.statistics = ROCKSDB_NAMESPACE::CreateDBStatistics();
options.merge_operator.reset(
new StringAppendTESTOperator(/*delim_char=*/' '));
DestroyAndReopen(options);
ASSERT_OK(Put("foo", "value"));
ASSERT_OK(Put("bar", "value"));
{
std::unique_ptr<Iterator> it(db_->NewIterator(ReadOptions()));
it->SeekToLast();
it->Prev();
it->Next();
}
ASSERT_EQ(1,
options.statistics->getTickerCount(NUMBER_OF_RESEEKS_IN_ITERATION));
const std::string merge_key("good");
ASSERT_OK(Put(merge_key, "orig"));
ASSERT_OK(Merge(merge_key, "suffix"));
{
std::unique_ptr<Iterator> it(db_->NewIterator(ReadOptions()));
it->Seek(merge_key);
ASSERT_TRUE(it->Valid());
const uint64_t prev_reseek_count =
options.statistics->getTickerCount(NUMBER_OF_RESEEKS_IN_ITERATION);
it->Prev();
ASSERT_EQ(prev_reseek_count + 1, options.statistics->getTickerCount(
NUMBER_OF_RESEEKS_IN_ITERATION));
}
}
TEST_P(DBIteratorTest, IterSmallAndLargeMix) {
do {
CreateAndReopenWithCF({"pikachu"}, CurrentOptions());
ASSERT_OK(Put(1, "a", "va"));
ASSERT_OK(Put(1, "b", std::string(100000, 'b')));
ASSERT_OK(Put(1, "c", "vc"));
ASSERT_OK(Put(1, "d", std::string(100000, 'd')));
ASSERT_OK(Put(1, "e", std::string(100000, 'e')));
Iterator* iter = NewIterator(ReadOptions(), handles_[1]);
iter->SeekToFirst();
ASSERT_EQ(IterStatus(iter), "a->va");
iter->Next();
ASSERT_EQ(IterStatus(iter), "b->" + std::string(100000, 'b'));
iter->Next();
ASSERT_EQ(IterStatus(iter), "c->vc");
iter->Next();
ASSERT_EQ(IterStatus(iter), "d->" + std::string(100000, 'd'));
iter->Next();
ASSERT_EQ(IterStatus(iter), "e->" + std::string(100000, 'e'));
iter->Next();
ASSERT_EQ(IterStatus(iter), "(invalid)");
iter->SeekToLast();
ASSERT_EQ(IterStatus(iter), "e->" + std::string(100000, 'e'));
iter->Prev();
ASSERT_EQ(IterStatus(iter), "d->" + std::string(100000, 'd'));
iter->Prev();
ASSERT_EQ(IterStatus(iter), "c->vc");
iter->Prev();
ASSERT_EQ(IterStatus(iter), "b->" + std::string(100000, 'b'));
iter->Prev();
ASSERT_EQ(IterStatus(iter), "a->va");
iter->Prev();
ASSERT_EQ(IterStatus(iter), "(invalid)");
delete iter;
} while (ChangeCompactOptions());
}
TEST_P(DBIteratorTest, IterMultiWithDelete) {
do {
CreateAndReopenWithCF({"pikachu"}, CurrentOptions());
ASSERT_OK(Put(1, "ka", "va"));
ASSERT_OK(Put(1, "kb", "vb"));
ASSERT_OK(Put(1, "kc", "vc"));
ASSERT_OK(Delete(1, "kb"));
ASSERT_EQ("NOT_FOUND", Get(1, "kb"));
Iterator* iter = NewIterator(ReadOptions(), handles_[1]);
iter->Seek("kc");
ASSERT_EQ(IterStatus(iter), "kc->vc");
if (!CurrentOptions().merge_operator) {
// TODO: merge operator does not support backward iteration yet
if (kPlainTableAllBytesPrefix != option_config_ &&
kBlockBasedTableWithWholeKeyHashIndex != option_config_ &&
kHashLinkList != option_config_ &&
kHashSkipList != option_config_) { // doesn't support SeekToLast
iter->Prev();
ASSERT_EQ(IterStatus(iter), "ka->va");
}
}
delete iter;
} while (ChangeOptions());
}
TEST_P(DBIteratorTest, IterPrevMaxSkip) {
do {
CreateAndReopenWithCF({"pikachu"}, CurrentOptions());
for (int i = 0; i < 2; i++) {
ASSERT_OK(Put(1, "key1", "v1"));
ASSERT_OK(Put(1, "key2", "v2"));
ASSERT_OK(Put(1, "key3", "v3"));
ASSERT_OK(Put(1, "key4", "v4"));
ASSERT_OK(Put(1, "key5", "v5"));
}
VerifyIterLast("key5->v5", 1);
ASSERT_OK(Delete(1, "key5"));
VerifyIterLast("key4->v4", 1);
ASSERT_OK(Delete(1, "key4"));
VerifyIterLast("key3->v3", 1);
ASSERT_OK(Delete(1, "key3"));
VerifyIterLast("key2->v2", 1);
ASSERT_OK(Delete(1, "key2"));
VerifyIterLast("key1->v1", 1);
ASSERT_OK(Delete(1, "key1"));
VerifyIterLast("(invalid)", 1);
} while (ChangeOptions(kSkipMergePut | kSkipNoSeekToLast));
}
TEST_P(DBIteratorTest, IterWithSnapshot) {
anon::OptionsOverride options_override;
options_override.skip_policy = kSkipNoSnapshot;
do {
CreateAndReopenWithCF({"pikachu"}, CurrentOptions(options_override));
ASSERT_OK(Put(1, "key1", "val1"));
ASSERT_OK(Put(1, "key2", "val2"));
ASSERT_OK(Put(1, "key3", "val3"));
ASSERT_OK(Put(1, "key4", "val4"));
ASSERT_OK(Put(1, "key5", "val5"));
const Snapshot* snapshot = db_->GetSnapshot();
ReadOptions options;
options.snapshot = snapshot;
Iterator* iter = NewIterator(options, handles_[1]);
ASSERT_OK(Put(1, "key0", "val0"));
// Put more values after the snapshot
ASSERT_OK(Put(1, "key100", "val100"));
ASSERT_OK(Put(1, "key101", "val101"));
iter->Seek("key5");
ASSERT_EQ(IterStatus(iter), "key5->val5");
if (!CurrentOptions().merge_operator) {
// TODO: merge operator does not support backward iteration yet
if (kPlainTableAllBytesPrefix != option_config_ &&
kBlockBasedTableWithWholeKeyHashIndex != option_config_ &&
kHashLinkList != option_config_ && kHashSkipList != option_config_) {
iter->Prev();
ASSERT_EQ(IterStatus(iter), "key4->val4");
iter->Prev();
ASSERT_EQ(IterStatus(iter), "key3->val3");
iter->Next();
ASSERT_EQ(IterStatus(iter), "key4->val4");
iter->Next();
ASSERT_EQ(IterStatus(iter), "key5->val5");
}
iter->Next();
ASSERT_TRUE(!iter->Valid());
}
if (!CurrentOptions().merge_operator) {
// TODO(gzh): merge operator does not support backward iteration yet
if (kPlainTableAllBytesPrefix != option_config_ &&
kBlockBasedTableWithWholeKeyHashIndex != option_config_ &&
kHashLinkList != option_config_ && kHashSkipList != option_config_) {
iter->SeekForPrev("key1");
ASSERT_EQ(IterStatus(iter), "key1->val1");
iter->Next();
ASSERT_EQ(IterStatus(iter), "key2->val2");
iter->Next();
ASSERT_EQ(IterStatus(iter), "key3->val3");
iter->Prev();
ASSERT_EQ(IterStatus(iter), "key2->val2");
iter->Prev();
ASSERT_EQ(IterStatus(iter), "key1->val1");
iter->Prev();
ASSERT_TRUE(!iter->Valid());
}
}
db_->ReleaseSnapshot(snapshot);
delete iter;
} while (ChangeOptions());
}
TEST_P(DBIteratorTest, IteratorPinsRef) {
do {
CreateAndReopenWithCF({"pikachu"}, CurrentOptions());
ASSERT_OK(Put(1, "foo", "hello"));
// Get iterator that will yield the current contents of the DB.
Iterator* iter = NewIterator(ReadOptions(), handles_[1]);
// Write to force compactions
ASSERT_OK(Put(1, "foo", "newvalue1"));
for (int i = 0; i < 100; i++) {
// 100K values
ASSERT_OK(Put(1, Key(i), Key(i) + std::string(100000, 'v')));
}
ASSERT_OK(Put(1, "foo", "newvalue2"));
iter->SeekToFirst();
ASSERT_TRUE(iter->Valid());
ASSERT_EQ("foo", iter->key().ToString());
ASSERT_EQ("hello", iter->value().ToString());
iter->Next();
ASSERT_TRUE(!iter->Valid());
delete iter;
} while (ChangeCompactOptions());
}
TEST_P(DBIteratorTest, IteratorDeleteAfterCfDelete) {
CreateAndReopenWithCF({"pikachu"}, CurrentOptions());
ASSERT_OK(Put(1, "foo", "delete-cf-then-delete-iter"));
ASSERT_OK(Put(1, "hello", "value2"));
ColumnFamilyHandle* cf = handles_[1];
ReadOptions ro;
auto* iter = db_->NewIterator(ro, cf);
iter->SeekToFirst();
ASSERT_EQ(IterStatus(iter), "foo->delete-cf-then-delete-iter");
// delete CF handle
EXPECT_OK(db_->DestroyColumnFamilyHandle(cf));
handles_.erase(std::begin(handles_) + 1);
// delete Iterator after CF handle is deleted
iter->Next();
ASSERT_EQ(IterStatus(iter), "hello->value2");
delete iter;
}
TEST_P(DBIteratorTest, IteratorDeleteAfterCfDrop) {
CreateAndReopenWithCF({"pikachu"}, CurrentOptions());
ASSERT_OK(Put(1, "foo", "drop-cf-then-delete-iter"));
ReadOptions ro;
ColumnFamilyHandle* cf = handles_[1];
auto* iter = db_->NewIterator(ro, cf);
iter->SeekToFirst();
ASSERT_EQ(IterStatus(iter), "foo->drop-cf-then-delete-iter");
// drop and delete CF
EXPECT_OK(db_->DropColumnFamily(cf));
EXPECT_OK(db_->DestroyColumnFamilyHandle(cf));
handles_.erase(std::begin(handles_) + 1);
// delete Iterator after CF handle is dropped
delete iter;
}
// SetOptions not defined in ROCKSDB LITE
#ifndef ROCKSDB_LITE
TEST_P(DBIteratorTest, DBIteratorBoundTest) {
Options options = CurrentOptions();
options.env = env_;
options.create_if_missing = true;
options.prefix_extractor = nullptr;
DestroyAndReopen(options);
ASSERT_OK(Put("a", "0"));
ASSERT_OK(Put("foo", "bar"));
ASSERT_OK(Put("foo1", "bar1"));
ASSERT_OK(Put("g1", "0"));
// testing basic case with no iterate_upper_bound and no prefix_extractor
{
ReadOptions ro;
ro.iterate_upper_bound = nullptr;
std::unique_ptr<Iterator> iter(NewIterator(ro));
iter->Seek("foo");
ASSERT_TRUE(iter->Valid());
ASSERT_EQ(iter->key().compare(Slice("foo")), 0);
iter->Next();
ASSERT_TRUE(iter->Valid());
ASSERT_EQ(iter->key().compare(Slice("foo1")), 0);
iter->Next();
ASSERT_TRUE(iter->Valid());
ASSERT_EQ(iter->key().compare(Slice("g1")), 0);
iter->SeekForPrev("g1");
ASSERT_TRUE(iter->Valid());
ASSERT_EQ(iter->key().compare(Slice("g1")), 0);
iter->Prev();
ASSERT_TRUE(iter->Valid());
ASSERT_EQ(iter->key().compare(Slice("foo1")), 0);
iter->Prev();
ASSERT_TRUE(iter->Valid());
ASSERT_EQ(iter->key().compare(Slice("foo")), 0);
}
// testing iterate_upper_bound and forward iterator
// to make sure it stops at bound
{
ReadOptions ro;
// iterate_upper_bound points beyond the last expected entry
Slice prefix("foo2");
ro.iterate_upper_bound = &prefix;
std::unique_ptr<Iterator> iter(NewIterator(ro));
iter->Seek("foo");
ASSERT_TRUE(iter->Valid());
ASSERT_EQ(iter->key().compare(Slice("foo")), 0);
iter->Next();
ASSERT_TRUE(iter->Valid());
ASSERT_EQ(iter->key().compare(("foo1")), 0);
iter->Next();
// should stop here...
ASSERT_TRUE(!iter->Valid());
}
// Testing SeekToLast with iterate_upper_bound set
{
ReadOptions ro;
Slice prefix("foo");
ro.iterate_upper_bound = &prefix;
std::unique_ptr<Iterator> iter(NewIterator(ro));
iter->SeekToLast();
ASSERT_TRUE(iter->Valid());
ASSERT_EQ(iter->key().compare(Slice("a")), 0);
}
// prefix is the first letter of the key
ASSERT_OK(dbfull()->SetOptions({{"prefix_extractor", "fixed:1"}}));
ASSERT_OK(Put("a", "0"));
ASSERT_OK(Put("foo", "bar"));
ASSERT_OK(Put("foo1", "bar1"));
ASSERT_OK(Put("g1", "0"));
// testing with iterate_upper_bound and prefix_extractor
// Seek target and iterate_upper_bound are not is same prefix
// This should be an error
{
ReadOptions ro;
Slice upper_bound("g");
ro.iterate_upper_bound = &upper_bound;
std::unique_ptr<Iterator> iter(NewIterator(ro));
iter->Seek("foo");
ASSERT_TRUE(iter->Valid());
ASSERT_EQ("foo", iter->key().ToString());
iter->Next();
ASSERT_TRUE(iter->Valid());
ASSERT_EQ("foo1", iter->key().ToString());
iter->Next();
ASSERT_TRUE(!iter->Valid());
}
// testing that iterate_upper_bound prevents iterating over deleted items
// if the bound has already reached
{
options.prefix_extractor = nullptr;
DestroyAndReopen(options);
ASSERT_OK(Put("a", "0"));
ASSERT_OK(Put("b", "0"));
ASSERT_OK(Put("b1", "0"));
ASSERT_OK(Put("c", "0"));
ASSERT_OK(Put("d", "0"));
ASSERT_OK(Put("e", "0"));
ASSERT_OK(Delete("c"));
ASSERT_OK(Delete("d"));
// base case with no bound
ReadOptions ro;
ro.iterate_upper_bound = nullptr;
std::unique_ptr<Iterator> iter(NewIterator(ro));
iter->Seek("b");
ASSERT_TRUE(iter->Valid());
ASSERT_EQ(iter->key().compare(Slice("b")), 0);
iter->Next();
ASSERT_TRUE(iter->Valid());
ASSERT_EQ(iter->key().compare(("b1")), 0);
get_perf_context()->Reset();
iter->Next();
ASSERT_TRUE(iter->Valid());
ASSERT_EQ(static_cast<int>(get_perf_context()->internal_delete_skipped_count), 2);
// now testing with iterate_bound
Slice prefix("c");
ro.iterate_upper_bound = &prefix;
iter.reset(NewIterator(ro));
get_perf_context()->Reset();
iter->Seek("b");
ASSERT_TRUE(iter->Valid());
ASSERT_EQ(iter->key().compare(Slice("b")), 0);
iter->Next();
ASSERT_TRUE(iter->Valid());
ASSERT_EQ(iter->key().compare(("b1")), 0);
iter->Next();
// the iteration should stop as soon as the bound key is reached
// even though the key is deleted
// hence internal_delete_skipped_count should be 0
ASSERT_TRUE(!iter->Valid());
ASSERT_EQ(static_cast<int>(get_perf_context()->internal_delete_skipped_count), 0);
}
}
TEST_P(DBIteratorTest, DBIteratorBoundMultiSeek) {
Options options = CurrentOptions();
options.env = env_;
options.create_if_missing = true;
options.statistics = ROCKSDB_NAMESPACE::CreateDBStatistics();
options.prefix_extractor = nullptr;
DestroyAndReopen(options);
ASSERT_OK(Put("a", "0"));
ASSERT_OK(Put("z", "0"));
ASSERT_OK(Flush());
ASSERT_OK(Put("foo1", "bar1"));
ASSERT_OK(Put("foo2", "bar2"));
ASSERT_OK(Put("foo3", "bar3"));
ASSERT_OK(Put("foo4", "bar4"));
{
std::string up_str = "foo5";
Slice up(up_str);
ReadOptions ro;
ro.iterate_upper_bound = &up;
std::unique_ptr<Iterator> iter(NewIterator(ro));
iter->Seek("foo1");
ASSERT_TRUE(iter->Valid());
ASSERT_EQ(iter->key().compare(Slice("foo1")), 0);
uint64_t prev_block_cache_hit =
TestGetTickerCount(options, BLOCK_CACHE_HIT);
uint64_t prev_block_cache_miss =
TestGetTickerCount(options, BLOCK_CACHE_MISS);
ASSERT_GT(prev_block_cache_hit + prev_block_cache_miss, 0);
iter->Seek("foo4");
ASSERT_TRUE(iter->Valid());
ASSERT_EQ(iter->key().compare(Slice("foo4")), 0);
ASSERT_EQ(prev_block_cache_hit,
TestGetTickerCount(options, BLOCK_CACHE_HIT));
ASSERT_EQ(prev_block_cache_miss,
TestGetTickerCount(options, BLOCK_CACHE_MISS));
iter->Seek("foo2");
ASSERT_TRUE(iter->Valid());
ASSERT_EQ(iter->key().compare(Slice("foo2")), 0);
iter->Next();
ASSERT_TRUE(iter->Valid());
ASSERT_EQ(iter->key().compare(Slice("foo3")), 0);
ASSERT_EQ(prev_block_cache_hit,
TestGetTickerCount(options, BLOCK_CACHE_HIT));
ASSERT_EQ(prev_block_cache_miss,
TestGetTickerCount(options, BLOCK_CACHE_MISS));
}
}
#endif
TEST_P(DBIteratorTest, DBIteratorBoundOptimizationTest) {
for (auto format_version : {2, 3, 4}) {
int upper_bound_hits = 0;
Options options = CurrentOptions();
ROCKSDB_NAMESPACE::SyncPoint::GetInstance()->SetCallBack(
"BlockBasedTableIterator:out_of_bound",
[&upper_bound_hits](void*) { upper_bound_hits++; });
ROCKSDB_NAMESPACE::SyncPoint::GetInstance()->EnableProcessing();
options.env = env_;
options.create_if_missing = true;
options.prefix_extractor = nullptr;
BlockBasedTableOptions table_options;
table_options.format_version = format_version;
table_options.flush_block_policy_factory =
std::make_shared<FlushBlockEveryKeyPolicyFactory>();
options.table_factory.reset(NewBlockBasedTableFactory(table_options));
DestroyAndReopen(options);
ASSERT_OK(Put("foo1", "bar1"));
ASSERT_OK(Put("foo2", "bar2"));
ASSERT_OK(Put("foo4", "bar4"));
ASSERT_OK(Flush());
Slice ub("foo3");
ReadOptions ro;
ro.iterate_upper_bound = &ub;
std::unique_ptr<Iterator> iter(NewIterator(ro));
iter->Seek("foo");
ASSERT_TRUE(iter->Valid());
ASSERT_EQ(iter->key().compare(Slice("foo1")), 0);
ASSERT_EQ(upper_bound_hits, 0);
iter->Next();
ASSERT_TRUE(iter->Valid());
ASSERT_EQ(iter->key().compare(Slice("foo2")), 0);
ASSERT_EQ(upper_bound_hits, 0);
iter->Next();
ASSERT_FALSE(iter->Valid());
ASSERT_EQ(upper_bound_hits, 1);
}
}
// Enable kBinarySearchWithFirstKey, do some iterator operations and check that
// they don't do unnecessary block reads.
TEST_P(DBIteratorTest, IndexWithFirstKey) {
for (int tailing = 0; tailing < 2; ++tailing) {
SCOPED_TRACE("tailing = " + std::to_string(tailing));
Options options = CurrentOptions();
options.env = env_;
options.create_if_missing = true;
options.prefix_extractor = nullptr;
options.merge_operator = MergeOperators::CreateStringAppendOperator();
options.statistics = ROCKSDB_NAMESPACE::CreateDBStatistics();
Statistics* stats = options.statistics.get();
BlockBasedTableOptions table_options;
table_options.index_type =
BlockBasedTableOptions::IndexType::kBinarySearchWithFirstKey;
table_options.index_shortening =
BlockBasedTableOptions::IndexShorteningMode::kNoShortening;
table_options.flush_block_policy_factory =
std::make_shared<FlushBlockEveryKeyPolicyFactory>();
table_options.block_cache =
NewLRUCache(8000); // fits all blocks and their cache metadata overhead
options.table_factory.reset(NewBlockBasedTableFactory(table_options));
DestroyAndReopen(options);
ASSERT_OK(Merge("a1", "x1"));
ASSERT_OK(Merge("b1", "y1"));
ASSERT_OK(Merge("c0", "z1"));
ASSERT_OK(Flush());
ASSERT_OK(Merge("a2", "x2"));
ASSERT_OK(Merge("b2", "y2"));
ASSERT_OK(Merge("c0", "z2"));
ASSERT_OK(Flush());
ASSERT_OK(Merge("a3", "x3"));
ASSERT_OK(Merge("b3", "y3"));
ASSERT_OK(Merge("c3", "z3"));
ASSERT_OK(Flush());
// Block cache is not important for this test.
// We use BLOCK_CACHE_DATA_* counters just because they're the most readily
// available way of counting block accesses.
ReadOptions ropt;
ropt.tailing = tailing;
std::unique_ptr<Iterator> iter(NewIterator(ropt));
ropt.read_tier = ReadTier::kBlockCacheTier;
std::unique_ptr<Iterator> nonblocking_iter(NewIterator(ropt));
iter->Seek("b10");
ASSERT_TRUE(iter->Valid());
EXPECT_EQ("b2", iter->key().ToString());
EXPECT_EQ("y2", iter->value().ToString());
EXPECT_EQ(1, stats->getTickerCount(BLOCK_CACHE_DATA_MISS));
// The cache-only iterator should succeed too, using the blocks pulled into
// the cache by the previous iterator.
nonblocking_iter->Seek("b10");
ASSERT_TRUE(nonblocking_iter->Valid());
EXPECT_EQ("b2", nonblocking_iter->key().ToString());
EXPECT_EQ("y2", nonblocking_iter->value().ToString());
EXPECT_EQ(1, stats->getTickerCount(BLOCK_CACHE_DATA_HIT));
// ... but it shouldn't be able to step forward since the next block is
// not in cache yet.
nonblocking_iter->Next();
ASSERT_FALSE(nonblocking_iter->Valid());
ASSERT_TRUE(nonblocking_iter->status().IsIncomplete());
// ... nor should a seek to the next key succeed.
nonblocking_iter->Seek("b20");
ASSERT_FALSE(nonblocking_iter->Valid());
ASSERT_TRUE(nonblocking_iter->status().IsIncomplete());
iter->Next();
ASSERT_TRUE(iter->Valid());
EXPECT_EQ("b3", iter->key().ToString());
EXPECT_EQ("y3", iter->value().ToString());
EXPECT_EQ(4, stats->getTickerCount(BLOCK_CACHE_DATA_MISS));
EXPECT_EQ(1, stats->getTickerCount(BLOCK_CACHE_DATA_HIT));
// After the blocking iterator loaded the next block, the nonblocking
// iterator's seek should succeed.
nonblocking_iter->Seek("b20");
ASSERT_TRUE(nonblocking_iter->Valid());
EXPECT_EQ("b3", nonblocking_iter->key().ToString());
EXPECT_EQ("y3", nonblocking_iter->value().ToString());
EXPECT_EQ(2, stats->getTickerCount(BLOCK_CACHE_DATA_HIT));
iter->Seek("c0");
ASSERT_TRUE(iter->Valid());
EXPECT_EQ("c0", iter->key().ToString());
EXPECT_EQ("z1,z2", iter->value().ToString());
EXPECT_EQ(2, stats->getTickerCount(BLOCK_CACHE_DATA_HIT));
EXPECT_EQ(6, stats->getTickerCount(BLOCK_CACHE_DATA_MISS));
iter->Next();
ASSERT_TRUE(iter->Valid());
EXPECT_EQ("c3", iter->key().ToString());
EXPECT_EQ("z3", iter->value().ToString());
EXPECT_EQ(2, stats->getTickerCount(BLOCK_CACHE_DATA_HIT));
EXPECT_EQ(7, stats->getTickerCount(BLOCK_CACHE_DATA_MISS));
iter.reset();
// Enable iterate_upper_bound and check that iterator is not trying to read
// blocks that are fully above upper bound.
std::string ub = "b3";
Slice ub_slice(ub);
ropt.iterate_upper_bound = &ub_slice;
iter.reset(NewIterator(ropt));
iter->Seek("b2");
ASSERT_TRUE(iter->Valid());
EXPECT_EQ("b2", iter->key().ToString());
EXPECT_EQ("y2", iter->value().ToString());
EXPECT_EQ(3, stats->getTickerCount(BLOCK_CACHE_DATA_HIT));
EXPECT_EQ(7, stats->getTickerCount(BLOCK_CACHE_DATA_MISS));
iter->Next();
ASSERT_FALSE(iter->Valid());
EXPECT_EQ(3, stats->getTickerCount(BLOCK_CACHE_DATA_HIT));
EXPECT_EQ(7, stats->getTickerCount(BLOCK_CACHE_DATA_MISS));
}
}
TEST_P(DBIteratorTest, IndexWithFirstKeyGet) {
Options options = CurrentOptions();
options.env = env_;
options.create_if_missing = true;
options.prefix_extractor = nullptr;
options.merge_operator = MergeOperators::CreateStringAppendOperator();
options.statistics = ROCKSDB_NAMESPACE::CreateDBStatistics();
Statistics* stats = options.statistics.get();
BlockBasedTableOptions table_options;
table_options.index_type =
BlockBasedTableOptions::IndexType::kBinarySearchWithFirstKey;
table_options.index_shortening =
BlockBasedTableOptions::IndexShorteningMode::kNoShortening;
table_options.flush_block_policy_factory =
std::make_shared<FlushBlockEveryKeyPolicyFactory>();
table_options.block_cache = NewLRUCache(1000); // fits all blocks
options.table_factory.reset(NewBlockBasedTableFactory(table_options));
DestroyAndReopen(options);
ASSERT_OK(Merge("a", "x1"));
ASSERT_OK(Merge("c", "y1"));
ASSERT_OK(Merge("e", "z1"));
ASSERT_OK(Flush());
ASSERT_OK(Merge("c", "y2"));
ASSERT_OK(Merge("e", "z2"));
ASSERT_OK(Flush());
// Get() between blocks shouldn't read any blocks.
ASSERT_EQ("NOT_FOUND", Get("b"));
EXPECT_EQ(0, stats->getTickerCount(BLOCK_CACHE_DATA_MISS));
EXPECT_EQ(0, stats->getTickerCount(BLOCK_CACHE_DATA_HIT));
// Get() of an existing key shouldn't read any unnecessary blocks when there's
// only one key per block.
ASSERT_EQ("y1,y2", Get("c"));
EXPECT_EQ(2, stats->getTickerCount(BLOCK_CACHE_DATA_MISS));
EXPECT_EQ(0, stats->getTickerCount(BLOCK_CACHE_DATA_HIT));
ASSERT_EQ("x1", Get("a"));
EXPECT_EQ(3, stats->getTickerCount(BLOCK_CACHE_DATA_MISS));
EXPECT_EQ(0, stats->getTickerCount(BLOCK_CACHE_DATA_HIT));
EXPECT_EQ(std::vector<std::string>({"NOT_FOUND", "z1,z2"}),
MultiGet({"b", "e"}));
}
// TODO(3.13): fix the issue of Seek() + Prev() which might not necessary
// return the biggest key which is smaller than the seek key.
TEST_P(DBIteratorTest, PrevAfterAndNextAfterMerge) {
Options options;
options.create_if_missing = true;
options.merge_operator = MergeOperators::CreatePutOperator();
options.env = env_;
DestroyAndReopen(options);
// write three entries with different keys using Merge()
WriteOptions wopts;
ASSERT_OK(db_->Merge(wopts, "1", "data1"));
ASSERT_OK(db_->Merge(wopts, "2", "data2"));
ASSERT_OK(db_->Merge(wopts, "3", "data3"));
std::unique_ptr<Iterator> it(NewIterator(ReadOptions()));
it->Seek("2");
ASSERT_TRUE(it->Valid());
ASSERT_EQ("2", it->key().ToString());
it->Prev();
ASSERT_TRUE(it->Valid());
ASSERT_EQ("1", it->key().ToString());
it->SeekForPrev("1");
ASSERT_TRUE(it->Valid());
ASSERT_EQ("1", it->key().ToString());
it->Next();
ASSERT_TRUE(it->Valid());
ASSERT_EQ("2", it->key().ToString());
}
class DBIteratorTestForPinnedData : public DBIteratorTest {
public:
enum TestConfig {
NORMAL,
CLOSE_AND_OPEN,
COMPACT_BEFORE_READ,
FLUSH_EVERY_1000,
MAX
};
DBIteratorTestForPinnedData() : DBIteratorTest() {}
void PinnedDataIteratorRandomized(TestConfig run_config) {
// Generate Random data
Random rnd(301);
int puts = 100000;
int key_pool = static_cast<int>(puts * 0.7);
int key_size = 100;
int val_size = 1000;
int seeks_percentage = 20; // 20% of keys will be used to test seek()
int delete_percentage = 20; // 20% of keys will be deleted
int merge_percentage = 20; // 20% of keys will be added using Merge()
Options options = CurrentOptions();
BlockBasedTableOptions table_options;
table_options.use_delta_encoding = false;
options.table_factory.reset(NewBlockBasedTableFactory(table_options));
options.merge_operator = MergeOperators::CreatePutOperator();
DestroyAndReopen(options);
std::vector<std::string> generated_keys(key_pool);
for (int i = 0; i < key_pool; i++) {
generated_keys[i] = rnd.RandomString(key_size);
}
std::map<std::string, std::string> true_data;
std::vector<std::string> random_keys;
std::vector<std::string> deleted_keys;
for (int i = 0; i < puts; i++) {
auto& k = generated_keys[rnd.Next() % key_pool];
auto v = rnd.RandomString(val_size);
// Insert data to true_data map and to DB
true_data[k] = v;
if (rnd.PercentTrue(merge_percentage)) {
ASSERT_OK(db_->Merge(WriteOptions(), k, v));
} else {
ASSERT_OK(Put(k, v));
}
// Pick random keys to be used to test Seek()
if (rnd.PercentTrue(seeks_percentage)) {
random_keys.push_back(k);
}
// Delete some random keys
if (rnd.PercentTrue(delete_percentage)) {
deleted_keys.push_back(k);
true_data.erase(k);
ASSERT_OK(Delete(k));
}
if (run_config == TestConfig::FLUSH_EVERY_1000) {
if (i && i % 1000 == 0) {
ASSERT_OK(Flush());
}
}
}
if (run_config == TestConfig::CLOSE_AND_OPEN) {
Close();
Reopen(options);
} else if (run_config == TestConfig::COMPACT_BEFORE_READ) {
ASSERT_OK(db_->CompactRange(CompactRangeOptions(), nullptr, nullptr));
}
ReadOptions ro;
ro.pin_data = true;
auto iter = NewIterator(ro);
{
// Test Seek to random keys
std::vector<Slice> keys_slices;
std::vector<std::string> true_keys;
for (auto& k : random_keys) {
iter->Seek(k);
if (!iter->Valid()) {
ASSERT_EQ(true_data.lower_bound(k), true_data.end());
continue;
}
std::string prop_value;
ASSERT_OK(
iter->GetProperty("rocksdb.iterator.is-key-pinned", &prop_value));
ASSERT_EQ("1", prop_value);
keys_slices.push_back(iter->key());
true_keys.push_back(true_data.lower_bound(k)->first);
}
for (size_t i = 0; i < keys_slices.size(); i++) {
ASSERT_EQ(keys_slices[i].ToString(), true_keys[i]);
}
}
{
// Test SeekForPrev to random keys
std::vector<Slice> keys_slices;
std::vector<std::string> true_keys;
for (auto& k : random_keys) {
iter->SeekForPrev(k);
if (!iter->Valid()) {
ASSERT_EQ(true_data.upper_bound(k), true_data.begin());
continue;
}
std::string prop_value;
ASSERT_OK(
iter->GetProperty("rocksdb.iterator.is-key-pinned", &prop_value));
ASSERT_EQ("1", prop_value);
keys_slices.push_back(iter->key());
true_keys.push_back((--true_data.upper_bound(k))->first);
}
for (size_t i = 0; i < keys_slices.size(); i++) {
ASSERT_EQ(keys_slices[i].ToString(), true_keys[i]);
}
}
{
// Test iterating all data forward
std::vector<Slice> all_keys;
for (iter->SeekToFirst(); iter->Valid(); iter->Next()) {
std::string prop_value;
ASSERT_OK(
iter->GetProperty("rocksdb.iterator.is-key-pinned", &prop_value));
ASSERT_EQ("1", prop_value);
all_keys.push_back(iter->key());
}
ASSERT_EQ(all_keys.size(), true_data.size());
// Verify that all keys slices are valid
auto data_iter = true_data.begin();
for (size_t i = 0; i < all_keys.size(); i++) {
ASSERT_EQ(all_keys[i].ToString(), data_iter->first);
data_iter++;
}
}
{
// Test iterating all data backward
std::vector<Slice> all_keys;
for (iter->SeekToLast(); iter->Valid(); iter->Prev()) {
std::string prop_value;
ASSERT_OK(
iter->GetProperty("rocksdb.iterator.is-key-pinned", &prop_value));
ASSERT_EQ("1", prop_value);
all_keys.push_back(iter->key());
}
ASSERT_EQ(all_keys.size(), true_data.size());
// Verify that all keys slices are valid (backward)
auto data_iter = true_data.rbegin();
for (size_t i = 0; i < all_keys.size(); i++) {
ASSERT_EQ(all_keys[i].ToString(), data_iter->first);
data_iter++;
}
}
delete iter;
}
};
#if !defined(ROCKSDB_VALGRIND_RUN) || defined(ROCKSDB_FULL_VALGRIND_RUN)
TEST_P(DBIteratorTestForPinnedData, PinnedDataIteratorRandomizedNormal) {
PinnedDataIteratorRandomized(TestConfig::NORMAL);
}
#endif // !defined(ROCKSDB_VALGRIND_RUN) || defined(ROCKSDB_FULL_VALGRIND_RUN)
TEST_P(DBIteratorTestForPinnedData, PinnedDataIteratorRandomizedCLoseAndOpen) {
PinnedDataIteratorRandomized(TestConfig::CLOSE_AND_OPEN);
}
TEST_P(DBIteratorTestForPinnedData,
PinnedDataIteratorRandomizedCompactBeforeRead) {
PinnedDataIteratorRandomized(TestConfig::COMPACT_BEFORE_READ);
}
TEST_P(DBIteratorTestForPinnedData, PinnedDataIteratorRandomizedFlush) {
PinnedDataIteratorRandomized(TestConfig::FLUSH_EVERY_1000);
}
INSTANTIATE_TEST_CASE_P(DBIteratorTestForPinnedDataInstance,
DBIteratorTestForPinnedData,
testing::Values(true, false));
#ifndef ROCKSDB_LITE
TEST_P(DBIteratorTest, PinnedDataIteratorMultipleFiles) {
Options options = CurrentOptions();
BlockBasedTableOptions table_options;
table_options.use_delta_encoding = false;
options.table_factory.reset(NewBlockBasedTableFactory(table_options));
options.disable_auto_compactions = true;
options.write_buffer_size = 1024 * 1024 * 10; // 10 Mb
DestroyAndReopen(options);
std::map<std::string, std::string> true_data;
// Generate 4 sst files in L2
Random rnd(301);
for (int i = 1; i <= 1000; i++) {
std::string k = Key(i * 3);
std::string v = rnd.RandomString(100);
ASSERT_OK(Put(k, v));
true_data[k] = v;
if (i % 250 == 0) {
ASSERT_OK(Flush());
}
}
ASSERT_EQ(FilesPerLevel(0), "4");
ASSERT_OK(db_->CompactRange(CompactRangeOptions(), nullptr, nullptr));
ASSERT_EQ(FilesPerLevel(0), "0,4");
// Generate 4 sst files in L0
for (int i = 1; i <= 1000; i++) {
std::string k = Key(i * 2);
std::string v = rnd.RandomString(100);
ASSERT_OK(Put(k, v));
true_data[k] = v;
if (i % 250 == 0) {
ASSERT_OK(Flush());
}
}
ASSERT_EQ(FilesPerLevel(0), "4,4");
// Add some keys/values in memtables
for (int i = 1; i <= 1000; i++) {
std::string k = Key(i);
std::string v = rnd.RandomString(100);
ASSERT_OK(Put(k, v));
true_data[k] = v;
}
ASSERT_EQ(FilesPerLevel(0), "4,4");
ReadOptions ro;
ro.pin_data = true;
auto iter = NewIterator(ro);
std::vector<std::pair<Slice, std::string>> results;
for (iter->SeekToFirst(); iter->Valid(); iter->Next()) {
std::string prop_value;
ASSERT_OK(iter->GetProperty("rocksdb.iterator.is-key-pinned", &prop_value));
ASSERT_EQ("1", prop_value);
results.emplace_back(iter->key(), iter->value().ToString());
}
ASSERT_EQ(results.size(), true_data.size());
auto data_iter = true_data.begin();
for (size_t i = 0; i < results.size(); i++, data_iter++) {
auto& kv = results[i];
ASSERT_EQ(kv.first, data_iter->first);
ASSERT_EQ(kv.second, data_iter->second);
}
delete iter;
}
#endif
TEST_P(DBIteratorTest, PinnedDataIteratorMergeOperator) {
Options options = CurrentOptions();
BlockBasedTableOptions table_options;
table_options.use_delta_encoding = false;
options.table_factory.reset(NewBlockBasedTableFactory(table_options));
options.merge_operator = MergeOperators::CreateUInt64AddOperator();
DestroyAndReopen(options);
std::string numbers[7];
for (int val = 0; val <= 6; val++) {
PutFixed64(numbers + val, val);
}
// +1 all keys in range [ 0 => 999]
for (int i = 0; i < 1000; i++) {
WriteOptions wo;
ASSERT_OK(db_->Merge(wo, Key(i), numbers[1]));
}
// +2 all keys divisible by 2 in range [ 0 => 999]
for (int i = 0; i < 1000; i += 2) {
WriteOptions wo;
ASSERT_OK(db_->Merge(wo, Key(i), numbers[2]));
}
// +3 all keys divisible by 5 in range [ 0 => 999]
for (int i = 0; i < 1000; i += 5) {
WriteOptions wo;
ASSERT_OK(db_->Merge(wo, Key(i), numbers[3]));
}
ReadOptions ro;
ro.pin_data = true;
auto iter = NewIterator(ro);
std::vector<std::pair<Slice, std::string>> results;
for (iter->SeekToFirst(); iter->Valid(); iter->Next()) {
std::string prop_value;
ASSERT_OK(iter->GetProperty("rocksdb.iterator.is-key-pinned", &prop_value));
ASSERT_EQ("1", prop_value);
results.emplace_back(iter->key(), iter->value().ToString());
}
ASSERT_EQ(results.size(), 1000);
for (size_t i = 0; i < results.size(); i++) {
auto& kv = results[i];
ASSERT_EQ(kv.first, Key(static_cast<int>(i)));
int expected_val = 1;
if (i % 2 == 0) {
expected_val += 2;
}
if (i % 5 == 0) {
expected_val += 3;
}
ASSERT_EQ(kv.second, numbers[expected_val]);
}
delete iter;
}
TEST_P(DBIteratorTest, PinnedDataIteratorReadAfterUpdate) {
Options options = CurrentOptions();
BlockBasedTableOptions table_options;
table_options.use_delta_encoding = false;
options.table_factory.reset(NewBlockBasedTableFactory(table_options));
options.write_buffer_size = 100000;
DestroyAndReopen(options);
Random rnd(301);
std::map<std::string, std::string> true_data;
for (int i = 0; i < 1000; i++) {
std::string k = rnd.RandomString(10);
std::string v = rnd.RandomString(1000);
ASSERT_OK(Put(k, v));
true_data[k] = v;
}
ReadOptions ro;
ro.pin_data = true;
auto iter = NewIterator(ro);
// Delete 50% of the keys and update the other 50%
for (auto& kv : true_data) {
if (rnd.OneIn(2)) {
ASSERT_OK(Delete(kv.first));
} else {
std::string new_val = rnd.RandomString(1000);
ASSERT_OK(Put(kv.first, new_val));
}
}
std::vector<std::pair<Slice, std::string>> results;
for (iter->SeekToFirst(); iter->Valid(); iter->Next()) {
std::string prop_value;
ASSERT_OK(iter->GetProperty("rocksdb.iterator.is-key-pinned", &prop_value));
ASSERT_EQ("1", prop_value);
results.emplace_back(iter->key(), iter->value().ToString());
}
auto data_iter = true_data.begin();
for (size_t i = 0; i < results.size(); i++, data_iter++) {
auto& kv = results[i];
ASSERT_EQ(kv.first, data_iter->first);
ASSERT_EQ(kv.second, data_iter->second);
}
delete iter;
}
class SliceTransformLimitedDomainGeneric : public SliceTransform {
const char* Name() const override {
return "SliceTransformLimitedDomainGeneric";
}
Slice Transform(const Slice& src) const override {
return Slice(src.data(), 1);
}
bool InDomain(const Slice& src) const override {
// prefix will be x????
return src.size() >= 1;
}
bool InRange(const Slice& dst) const override {
// prefix will be x????
return dst.size() == 1;
}
};
TEST_P(DBIteratorTest, IterSeekForPrevCrossingFiles) {
Options options = CurrentOptions();
options.prefix_extractor.reset(NewFixedPrefixTransform(1));
options.disable_auto_compactions = true;
// Enable prefix bloom for SST files
BlockBasedTableOptions table_options;
table_options.filter_policy.reset(NewBloomFilterPolicy(10, true));
options.table_factory.reset(NewBlockBasedTableFactory(table_options));
DestroyAndReopen(options);
ASSERT_OK(Put("a1", "va1"));
ASSERT_OK(Put("a2", "va2"));
ASSERT_OK(Put("a3", "va3"));
ASSERT_OK(Flush());
ASSERT_OK(Put("b1", "vb1"));
ASSERT_OK(Put("b2", "vb2"));
ASSERT_OK(Put("b3", "vb3"));
ASSERT_OK(Flush());
ASSERT_OK(Put("b4", "vb4"));
ASSERT_OK(Put("d1", "vd1"));
ASSERT_OK(Put("d2", "vd2"));
ASSERT_OK(Put("d4", "vd4"));
ASSERT_OK(Flush());
MoveFilesToLevel(1);
{
ReadOptions ro;
Iterator* iter = NewIterator(ro);
iter->SeekForPrev("a4");
ASSERT_EQ(iter->key().ToString(), "a3");
ASSERT_EQ(iter->value().ToString(), "va3");
iter->SeekForPrev("c2");
ASSERT_EQ(iter->key().ToString(), "b3");
iter->SeekForPrev("d3");
ASSERT_EQ(iter->key().ToString(), "d2");
iter->SeekForPrev("b5");
ASSERT_EQ(iter->key().ToString(), "b4");
delete iter;
}
{
ReadOptions ro;
ro.prefix_same_as_start = true;
Iterator* iter = NewIterator(ro);
iter->SeekForPrev("c2");
ASSERT_TRUE(!iter->Valid());
ASSERT_OK(iter->status());
delete iter;
}
}
TEST_P(DBIteratorTest, IterSeekForPrevCrossingFilesCustomPrefixExtractor) {
Options options = CurrentOptions();
options.prefix_extractor =
std::make_shared<SliceTransformLimitedDomainGeneric>();
options.disable_auto_compactions = true;
// Enable prefix bloom for SST files
BlockBasedTableOptions table_options;
table_options.filter_policy.reset(NewBloomFilterPolicy(10, true));
options.table_factory.reset(NewBlockBasedTableFactory(table_options));
DestroyAndReopen(options);
ASSERT_OK(Put("a1", "va1"));
ASSERT_OK(Put("a2", "va2"));
ASSERT_OK(Put("a3", "va3"));
ASSERT_OK(Flush());
ASSERT_OK(Put("b1", "vb1"));
ASSERT_OK(Put("b2", "vb2"));
ASSERT_OK(Put("b3", "vb3"));
ASSERT_OK(Flush());
ASSERT_OK(Put("b4", "vb4"));
ASSERT_OK(Put("d1", "vd1"));
ASSERT_OK(Put("d2", "vd2"));
ASSERT_OK(Put("d4", "vd4"));
ASSERT_OK(Flush());
MoveFilesToLevel(1);
{
ReadOptions ro;
Iterator* iter = NewIterator(ro);
iter->SeekForPrev("a4");
ASSERT_EQ(iter->key().ToString(), "a3");
ASSERT_EQ(iter->value().ToString(), "va3");
iter->SeekForPrev("c2");
ASSERT_EQ(iter->key().ToString(), "b3");
iter->SeekForPrev("d3");
ASSERT_EQ(iter->key().ToString(), "d2");
iter->SeekForPrev("b5");
ASSERT_EQ(iter->key().ToString(), "b4");
delete iter;
}
{
ReadOptions ro;
ro.prefix_same_as_start = true;
Iterator* iter = NewIterator(ro);
iter->SeekForPrev("c2");
ASSERT_TRUE(!iter->Valid());
ASSERT_OK(iter->status());
delete iter;
}
}
TEST_P(DBIteratorTest, IterPrevKeyCrossingBlocks) {
Options options = CurrentOptions();
BlockBasedTableOptions table_options;
table_options.block_size = 1; // every block will contain one entry
options.table_factory.reset(NewBlockBasedTableFactory(table_options));
options.merge_operator = MergeOperators::CreateStringAppendTESTOperator();
options.disable_auto_compactions = true;
options.max_sequential_skip_in_iterations = 8;
DestroyAndReopen(options);
// Putting such deletes will force DBIter::Prev() to fallback to a Seek
for (int file_num = 0; file_num < 10; file_num++) {
ASSERT_OK(Delete("key4"));
ASSERT_OK(Flush());
}
// First File containing 5 blocks of puts
ASSERT_OK(Put("key1", "val1.0"));
ASSERT_OK(Put("key2", "val2.0"));
ASSERT_OK(Put("key3", "val3.0"));
ASSERT_OK(Put("key4", "val4.0"));
ASSERT_OK(Put("key5", "val5.0"));
ASSERT_OK(Flush());
// Second file containing 9 blocks of merge operands
ASSERT_OK(db_->Merge(WriteOptions(), "key1", "val1.1"));
ASSERT_OK(db_->Merge(WriteOptions(), "key1", "val1.2"));
ASSERT_OK(db_->Merge(WriteOptions(), "key2", "val2.1"));
ASSERT_OK(db_->Merge(WriteOptions(), "key2", "val2.2"));
ASSERT_OK(db_->Merge(WriteOptions(), "key2", "val2.3"));
ASSERT_OK(db_->Merge(WriteOptions(), "key3", "val3.1"));
ASSERT_OK(db_->Merge(WriteOptions(), "key3", "val3.2"));
ASSERT_OK(db_->Merge(WriteOptions(), "key3", "val3.3"));
ASSERT_OK(db_->Merge(WriteOptions(), "key3", "val3.4"));
ASSERT_OK(Flush());
{
ReadOptions ro;
ro.fill_cache = false;
Iterator* iter = NewIterator(ro);
iter->SeekToLast();
ASSERT_EQ(iter->key().ToString(), "key5");
ASSERT_EQ(iter->value().ToString(), "val5.0");
iter->Prev();
ASSERT_EQ(iter->key().ToString(), "key4");
ASSERT_EQ(iter->value().ToString(), "val4.0");
iter->Prev();
ASSERT_EQ(iter->key().ToString(), "key3");
ASSERT_EQ(iter->value().ToString(), "val3.0,val3.1,val3.2,val3.3,val3.4");
iter->Prev();
ASSERT_EQ(iter->key().ToString(), "key2");
ASSERT_EQ(iter->value().ToString(), "val2.0,val2.1,val2.2,val2.3");
iter->Prev();
ASSERT_EQ(iter->key().ToString(), "key1");
ASSERT_EQ(iter->value().ToString(), "val1.0,val1.1,val1.2");
delete iter;
}
}
TEST_P(DBIteratorTest, IterPrevKeyCrossingBlocksRandomized) {
Options options = CurrentOptions();
options.merge_operator = MergeOperators::CreateStringAppendTESTOperator();
options.disable_auto_compactions = true;
options.level0_slowdown_writes_trigger = (1 << 30);
options.level0_stop_writes_trigger = (1 << 30);
options.max_sequential_skip_in_iterations = 8;
DestroyAndReopen(options);
const int kNumKeys = 500;
// Small number of merge operands to make sure that DBIter::Prev() don't
// fall back to Seek()
const int kNumMergeOperands = 3;
// Use value size that will make sure that every block contain 1 key
const int kValSize =
static_cast<int>(BlockBasedTableOptions().block_size) * 4;
// Percentage of keys that wont get merge operations
const int kNoMergeOpPercentage = 20;
// Percentage of keys that will be deleted
const int kDeletePercentage = 10;
// For half of the key range we will write multiple deletes first to
// force DBIter::Prev() to fall back to Seek()
for (int file_num = 0; file_num < 10; file_num++) {
for (int i = 0; i < kNumKeys; i += 2) {
ASSERT_OK(Delete(Key(i)));
}
ASSERT_OK(Flush());
}
Random rnd(301);
std::map<std::string, std::string> true_data;
std::string gen_key;
std::string gen_val;
for (int i = 0; i < kNumKeys; i++) {
gen_key = Key(i);
gen_val = rnd.RandomString(kValSize);
ASSERT_OK(Put(gen_key, gen_val));
true_data[gen_key] = gen_val;
}
ASSERT_OK(Flush());
// Separate values and merge operands in different file so that we
// make sure that we don't merge them while flushing but actually
// merge them in the read path
for (int i = 0; i < kNumKeys; i++) {
if (rnd.PercentTrue(kNoMergeOpPercentage)) {
// Dont give merge operations for some keys
continue;
}
for (int j = 0; j < kNumMergeOperands; j++) {
gen_key = Key(i);
gen_val = rnd.RandomString(kValSize);
ASSERT_OK(db_->Merge(WriteOptions(), gen_key, gen_val));
true_data[gen_key] += "," + gen_val;
}
}
ASSERT_OK(Flush());
for (int i = 0; i < kNumKeys; i++) {
if (rnd.PercentTrue(kDeletePercentage)) {
gen_key = Key(i);
ASSERT_OK(Delete(gen_key));
true_data.erase(gen_key);
}
}
ASSERT_OK(Flush());
{
ReadOptions ro;
ro.fill_cache = false;
Iterator* iter = NewIterator(ro);
auto data_iter = true_data.rbegin();
for (iter->SeekToLast(); iter->Valid(); iter->Prev()) {
ASSERT_EQ(iter->key().ToString(), data_iter->first);
ASSERT_EQ(iter->value().ToString(), data_iter->second);
data_iter++;
}
ASSERT_EQ(data_iter, true_data.rend());
delete iter;
}
{
ReadOptions ro;
ro.fill_cache = false;
Iterator* iter = NewIterator(ro);
auto data_iter = true_data.rbegin();
int entries_right = 0;
std::string seek_key;
for (iter->SeekToLast(); iter->Valid(); iter->Prev()) {
// Verify key/value of current position
ASSERT_EQ(iter->key().ToString(), data_iter->first);
ASSERT_EQ(iter->value().ToString(), data_iter->second);
bool restore_position_with_seek = rnd.Uniform(2);
if (restore_position_with_seek) {
seek_key = iter->key().ToString();
}
// Do some Next() operations the restore the iterator to orignal position
int next_count =
entries_right > 0 ? rnd.Uniform(std::min(entries_right, 10)) : 0;
for (int i = 0; i < next_count; i++) {
iter->Next();
data_iter--;
ASSERT_EQ(iter->key().ToString(), data_iter->first);
ASSERT_EQ(iter->value().ToString(), data_iter->second);
}
if (restore_position_with_seek) {
// Restore orignal position using Seek()
iter->Seek(seek_key);
for (int i = 0; i < next_count; i++) {
data_iter++;
}
ASSERT_EQ(iter->key().ToString(), data_iter->first);
ASSERT_EQ(iter->value().ToString(), data_iter->second);
} else {
// Restore original position using Prev()
for (int i = 0; i < next_count; i++) {
iter->Prev();
data_iter++;
ASSERT_EQ(iter->key().ToString(), data_iter->first);
ASSERT_EQ(iter->value().ToString(), data_iter->second);
}
}
entries_right++;
data_iter++;
}
ASSERT_EQ(data_iter, true_data.rend());
delete iter;
}
}
TEST_P(DBIteratorTest, IteratorWithLocalStatistics) {
Options options = CurrentOptions();
options.statistics = ROCKSDB_NAMESPACE::CreateDBStatistics();
DestroyAndReopen(options);
Random rnd(301);
for (int i = 0; i < 1000; i++) {
// Key 10 bytes / Value 10 bytes
ASSERT_OK(Put(rnd.RandomString(10), rnd.RandomString(10)));
}
std::atomic<uint64_t> total_next(0);
std::atomic<uint64_t> total_next_found(0);
std::atomic<uint64_t> total_prev(0);
std::atomic<uint64_t> total_prev_found(0);
std::atomic<uint64_t> total_bytes(0);
std::vector<port::Thread> threads;
std::function<void()> reader_func_next = [&]() {
SetPerfLevel(kEnableCount);
get_perf_context()->Reset();
Iterator* iter = NewIterator(ReadOptions());
iter->SeekToFirst();
// Seek will bump ITER_BYTES_READ
uint64_t bytes = 0;
bytes += iter->key().size();
bytes += iter->value().size();
while (true) {
iter->Next();
total_next++;
if (!iter->Valid()) {
break;
}
total_next_found++;
bytes += iter->key().size();
bytes += iter->value().size();
}
delete iter;
ASSERT_EQ(bytes, get_perf_context()->iter_read_bytes);
SetPerfLevel(kDisable);
total_bytes += bytes;
};
std::function<void()> reader_func_prev = [&]() {
SetPerfLevel(kEnableCount);
Iterator* iter = NewIterator(ReadOptions());
iter->SeekToLast();
// Seek will bump ITER_BYTES_READ
uint64_t bytes = 0;
bytes += iter->key().size();
bytes += iter->value().size();
while (true) {
iter->Prev();
total_prev++;
if (!iter->Valid()) {
break;
}
total_prev_found++;
bytes += iter->key().size();
bytes += iter->value().size();
}
delete iter;
ASSERT_EQ(bytes, get_perf_context()->iter_read_bytes);
SetPerfLevel(kDisable);
total_bytes += bytes;
};
for (int i = 0; i < 10; i++) {
threads.emplace_back(reader_func_next);
}
for (int i = 0; i < 15; i++) {
threads.emplace_back(reader_func_prev);
}
for (auto& t : threads) {
t.join();
}
ASSERT_EQ(TestGetTickerCount(options, NUMBER_DB_NEXT), (uint64_t)total_next);
ASSERT_EQ(TestGetTickerCount(options, NUMBER_DB_NEXT_FOUND),
(uint64_t)total_next_found);
ASSERT_EQ(TestGetTickerCount(options, NUMBER_DB_PREV), (uint64_t)total_prev);
ASSERT_EQ(TestGetTickerCount(options, NUMBER_DB_PREV_FOUND),
(uint64_t)total_prev_found);
ASSERT_EQ(TestGetTickerCount(options, ITER_BYTES_READ), (uint64_t)total_bytes);
}
TEST_P(DBIteratorTest, ReadAhead) {
Options options;
env_->count_random_reads_ = true;
options.env = env_;
options.disable_auto_compactions = true;
options.write_buffer_size = 4 << 20;
options.statistics = ROCKSDB_NAMESPACE::CreateDBStatistics();
BlockBasedTableOptions table_options;
table_options.block_size = 1024;
table_options.no_block_cache = true;
options.table_factory.reset(NewBlockBasedTableFactory(table_options));
Reopen(options);
std::string value(1024, 'a');
for (int i = 0; i < 100; i++) {
ASSERT_OK(Put(Key(i), value));
}
ASSERT_OK(Flush());
MoveFilesToLevel(2);
for (int i = 0; i < 100; i++) {
ASSERT_OK(Put(Key(i), value));
}
ASSERT_OK(Flush());
MoveFilesToLevel(1);
for (int i = 0; i < 100; i++) {
ASSERT_OK(Put(Key(i), value));
}
ASSERT_OK(Flush());
#ifndef ROCKSDB_LITE
ASSERT_EQ("1,1,1", FilesPerLevel());
#endif // !ROCKSDB_LITE
env_->random_read_bytes_counter_ = 0;
options.statistics->setTickerCount(NO_FILE_OPENS, 0);
ReadOptions read_options;
auto* iter = NewIterator(read_options);
iter->SeekToFirst();
int64_t num_file_opens = TestGetTickerCount(options, NO_FILE_OPENS);
size_t bytes_read = env_->random_read_bytes_counter_;
delete iter;
int64_t num_file_closes = TestGetTickerCount(options, NO_FILE_CLOSES);
env_->random_read_bytes_counter_ = 0;
options.statistics->setTickerCount(NO_FILE_OPENS, 0);
read_options.readahead_size = 1024 * 10;
iter = NewIterator(read_options);
iter->SeekToFirst();
int64_t num_file_opens_readahead = TestGetTickerCount(options, NO_FILE_OPENS);
size_t bytes_read_readahead = env_->random_read_bytes_counter_;
delete iter;
int64_t num_file_closes_readahead =
TestGetTickerCount(options, NO_FILE_CLOSES);
ASSERT_EQ(num_file_opens, num_file_opens_readahead);
ASSERT_EQ(num_file_closes, num_file_closes_readahead);
ASSERT_GT(bytes_read_readahead, bytes_read);
ASSERT_GT(bytes_read_readahead, read_options.readahead_size * 3);
// Verify correctness.
iter = NewIterator(read_options);
int count = 0;
for (iter->SeekToFirst(); iter->Valid(); iter->Next()) {
ASSERT_EQ(value, iter->value());
count++;
}
ASSERT_EQ(100, count);
for (int i = 0; i < 100; i++) {
iter->Seek(Key(i));
ASSERT_EQ(value, iter->value());
}
delete iter;
}
// Insert a key, create a snapshot iterator, overwrite key lots of times,
// seek to a smaller key. Expect DBIter to fall back to a seek instead of
// going through all the overwrites linearly.
TEST_P(DBIteratorTest, DBIteratorSkipRecentDuplicatesTest) {
Options options = CurrentOptions();
options.env = env_;
options.create_if_missing = true;
options.max_sequential_skip_in_iterations = 3;
options.prefix_extractor = nullptr;
options.write_buffer_size = 1 << 27; // big enough to avoid flush
options.statistics = ROCKSDB_NAMESPACE::CreateDBStatistics();
DestroyAndReopen(options);
// Insert.
ASSERT_OK(Put("b", "0"));
// Create iterator.
ReadOptions ro;
std::unique_ptr<Iterator> iter(NewIterator(ro));
// Insert a lot.
for (int i = 0; i < 100; ++i) {
ASSERT_OK(Put("b", std::to_string(i + 1).c_str()));
}
#ifndef ROCKSDB_LITE
// Check that memtable wasn't flushed.
std::string val;
ASSERT_TRUE(db_->GetProperty("rocksdb.num-files-at-level0", &val));
EXPECT_EQ("0", val);
#endif
// Seek iterator to a smaller key.
get_perf_context()->Reset();
iter->Seek("a");
ASSERT_TRUE(iter->Valid());
EXPECT_EQ("b", iter->key().ToString());
EXPECT_EQ("0", iter->value().ToString());
// Check that the seek didn't do too much work.
// Checks are not tight, just make sure that everything is well below 100.
EXPECT_LT(get_perf_context()->internal_key_skipped_count, 4);
EXPECT_LT(get_perf_context()->internal_recent_skipped_count, 8);
EXPECT_LT(get_perf_context()->seek_on_memtable_count, 10);
EXPECT_LT(get_perf_context()->next_on_memtable_count, 10);
EXPECT_LT(get_perf_context()->prev_on_memtable_count, 10);
// Check that iterator did something like what we expect.
EXPECT_EQ(get_perf_context()->internal_delete_skipped_count, 0);
EXPECT_EQ(get_perf_context()->internal_merge_count, 0);
EXPECT_GE(get_perf_context()->internal_recent_skipped_count, 2);
EXPECT_GE(get_perf_context()->seek_on_memtable_count, 2);
EXPECT_EQ(1, options.statistics->getTickerCount(
NUMBER_OF_RESEEKS_IN_ITERATION));
}
TEST_P(DBIteratorTest, Refresh) {
ASSERT_OK(Put("x", "y"));
std::unique_ptr<Iterator> iter(NewIterator(ReadOptions()));
ASSERT_OK(iter->status());
iter->Seek(Slice("a"));
ASSERT_TRUE(iter->Valid());
ASSERT_EQ(iter->key().compare(Slice("x")), 0);
iter->Next();
ASSERT_FALSE(iter->Valid());
ASSERT_OK(Put("c", "d"));
iter->Seek(Slice("a"));
ASSERT_TRUE(iter->Valid());
ASSERT_EQ(iter->key().compare(Slice("x")), 0);
iter->Next();
ASSERT_FALSE(iter->Valid());
ASSERT_OK(iter->status());
ASSERT_OK(iter->Refresh());
iter->Seek(Slice("a"));
ASSERT_TRUE(iter->Valid());
ASSERT_EQ(iter->key().compare(Slice("c")), 0);
iter->Next();
ASSERT_TRUE(iter->Valid());
ASSERT_EQ(iter->key().compare(Slice("x")), 0);
iter->Next();
ASSERT_FALSE(iter->Valid());
EXPECT_OK(dbfull()->Flush(FlushOptions()));
ASSERT_OK(Put("m", "n"));
iter->Seek(Slice("a"));
ASSERT_TRUE(iter->Valid());
ASSERT_EQ(iter->key().compare(Slice("c")), 0);
iter->Next();
ASSERT_TRUE(iter->Valid());
ASSERT_EQ(iter->key().compare(Slice("x")), 0);
iter->Next();
ASSERT_FALSE(iter->Valid());
ASSERT_OK(iter->status());
ASSERT_OK(iter->Refresh());
iter->Seek(Slice("a"));
ASSERT_TRUE(iter->Valid());
ASSERT_EQ(iter->key().compare(Slice("c")), 0);
iter->Next();
ASSERT_TRUE(iter->Valid());
ASSERT_EQ(iter->key().compare(Slice("m")), 0);
iter->Next();
ASSERT_TRUE(iter->Valid());
ASSERT_EQ(iter->key().compare(Slice("x")), 0);
iter->Next();
ASSERT_FALSE(iter->Valid());
iter.reset();
}
TEST_P(DBIteratorTest, RefreshWithSnapshot) {
ASSERT_OK(Put("x", "y"));
const Snapshot* snapshot = db_->GetSnapshot();
ReadOptions options;
options.snapshot = snapshot;
Iterator* iter = NewIterator(options);
ASSERT_OK(iter->status());
iter->Seek(Slice("a"));
ASSERT_TRUE(iter->Valid());
ASSERT_EQ(iter->key().compare(Slice("x")), 0);
iter->Next();
ASSERT_FALSE(iter->Valid());
ASSERT_OK(Put("c", "d"));
iter->Seek(Slice("a"));
ASSERT_TRUE(iter->Valid());
ASSERT_EQ(iter->key().compare(Slice("x")), 0);
iter->Next();
ASSERT_FALSE(iter->Valid());
ASSERT_OK(iter->status());
Status s = iter->Refresh();
ASSERT_TRUE(s.IsNotSupported());
db_->ReleaseSnapshot(snapshot);
delete iter;
}
TEST_P(DBIteratorTest, CreationFailure) {
SyncPoint::GetInstance()->SetCallBack(
"DBImpl::NewInternalIterator:StatusCallback", [](void* arg) {
*(reinterpret_cast<Status*>(arg)) = Status::Corruption("test status");
});
SyncPoint::GetInstance()->EnableProcessing();
Iterator* iter = NewIterator(ReadOptions());
ASSERT_FALSE(iter->Valid());
ASSERT_TRUE(iter->status().IsCorruption());
delete iter;
}
TEST_P(DBIteratorTest, UpperBoundWithChangeDirection) {
Options options = CurrentOptions();
options.max_sequential_skip_in_iterations = 3;
DestroyAndReopen(options);
// write a bunch of kvs to the database.
ASSERT_OK(Put("a", "1"));
ASSERT_OK(Put("y", "1"));
ASSERT_OK(Put("y1", "1"));
ASSERT_OK(Put("y2", "1"));
ASSERT_OK(Put("y3", "1"));
ASSERT_OK(Put("z", "1"));
ASSERT_OK(Flush());
ASSERT_OK(Put("a", "1"));
ASSERT_OK(Put("z", "1"));
ASSERT_OK(Put("bar", "1"));
ASSERT_OK(Put("foo", "1"));
std::string upper_bound = "x";
Slice ub_slice(upper_bound);
ReadOptions ro;
ro.iterate_upper_bound = &ub_slice;
ro.max_skippable_internal_keys = 1000;
Iterator* iter = NewIterator(ro);
iter->Seek("foo");
ASSERT_TRUE(iter->Valid());
ASSERT_EQ("foo", iter->key().ToString());
iter->Prev();
ASSERT_TRUE(iter->Valid());
ASSERT_OK(iter->status());
ASSERT_EQ("bar", iter->key().ToString());
delete iter;
}
TEST_P(DBIteratorTest, TableFilter) {
ASSERT_OK(Put("a", "1"));
EXPECT_OK(dbfull()->Flush(FlushOptions()));
ASSERT_OK(Put("b", "2"));
ASSERT_OK(Put("c", "3"));
EXPECT_OK(dbfull()->Flush(FlushOptions()));
ASSERT_OK(Put("d", "4"));
ASSERT_OK(Put("e", "5"));
ASSERT_OK(Put("f", "6"));
EXPECT_OK(dbfull()->Flush(FlushOptions()));
// Ensure the table_filter callback is called once for each table.
{
std::set<uint64_t> unseen{1, 2, 3};
ReadOptions opts;
opts.table_filter = [&](const TableProperties& props) {
auto it = unseen.find(props.num_entries);
if (it == unseen.end()) {
ADD_FAILURE() << "saw table properties with an unexpected "
<< props.num_entries << " entries";
} else {
unseen.erase(it);
}
return true;
};
auto iter = NewIterator(opts);
iter->SeekToFirst();
ASSERT_EQ(IterStatus(iter), "a->1");
iter->Next();
ASSERT_EQ(IterStatus(iter), "b->2");
iter->Next();
ASSERT_EQ(IterStatus(iter), "c->3");
iter->Next();
ASSERT_EQ(IterStatus(iter), "d->4");
iter->Next();
ASSERT_EQ(IterStatus(iter), "e->5");
iter->Next();
ASSERT_EQ(IterStatus(iter), "f->6");
iter->Next();
ASSERT_FALSE(iter->Valid());
ASSERT_TRUE(unseen.empty());
delete iter;
}
// Ensure returning false in the table_filter hides the keys from that table
// during iteration.
{
ReadOptions opts;
opts.table_filter = [](const TableProperties& props) {
return props.num_entries != 2;
};
auto iter = NewIterator(opts);
iter->SeekToFirst();
ASSERT_EQ(IterStatus(iter), "a->1");
iter->Next();
ASSERT_EQ(IterStatus(iter), "d->4");
iter->Next();
ASSERT_EQ(IterStatus(iter), "e->5");
iter->Next();
ASSERT_EQ(IterStatus(iter), "f->6");
iter->Next();
ASSERT_FALSE(iter->Valid());
delete iter;
}
}
TEST_P(DBIteratorTest, UpperBoundWithPrevReseek) {
Options options = CurrentOptions();
options.max_sequential_skip_in_iterations = 3;
DestroyAndReopen(options);
// write a bunch of kvs to the database.
ASSERT_OK(Put("a", "1"));
ASSERT_OK(Put("y", "1"));
ASSERT_OK(Put("z", "1"));
ASSERT_OK(Flush());
ASSERT_OK(Put("a", "1"));
ASSERT_OK(Put("z", "1"));
ASSERT_OK(Put("bar", "1"));
ASSERT_OK(Put("foo", "1"));
ASSERT_OK(Put("foo", "2"));
ASSERT_OK(Put("foo", "3"));
ASSERT_OK(Put("foo", "4"));
ASSERT_OK(Put("foo", "5"));
const Snapshot* snapshot = db_->GetSnapshot();
ASSERT_OK(Put("foo", "6"));
std::string upper_bound = "x";
Slice ub_slice(upper_bound);
ReadOptions ro;
ro.snapshot = snapshot;
ro.iterate_upper_bound = &ub_slice;
Iterator* iter = NewIterator(ro);
iter->SeekForPrev("goo");
ASSERT_TRUE(iter->Valid());
ASSERT_EQ("foo", iter->key().ToString());
iter->Prev();
ASSERT_TRUE(iter->Valid());
ASSERT_EQ("bar", iter->key().ToString());
delete iter;
db_->ReleaseSnapshot(snapshot);
}
TEST_P(DBIteratorTest, SkipStatistics) {
Options options = CurrentOptions();
options.statistics = ROCKSDB_NAMESPACE::CreateDBStatistics();
DestroyAndReopen(options);
int skip_count = 0;
// write a bunch of kvs to the database.
ASSERT_OK(Put("a", "1"));
ASSERT_OK(Put("b", "1"));
ASSERT_OK(Put("c", "1"));
ASSERT_OK(Flush());
ASSERT_OK(Put("d", "1"));
ASSERT_OK(Put("e", "1"));
ASSERT_OK(Put("f", "1"));
ASSERT_OK(Put("a", "2"));
ASSERT_OK(Put("b", "2"));
ASSERT_OK(Flush());
ASSERT_OK(Delete("d"));
ASSERT_OK(Delete("e"));
ASSERT_OK(Delete("f"));
Iterator* iter = NewIterator(ReadOptions());
int count = 0;
for (iter->SeekToFirst(); iter->Valid(); iter->Next()) {
ASSERT_OK(iter->status());
count++;
}
ASSERT_EQ(count, 3);
delete iter;
skip_count += 8; // 3 deletes + 3 original keys + 2 lower in sequence
ASSERT_EQ(skip_count, TestGetTickerCount(options, NUMBER_ITER_SKIP));
iter = NewIterator(ReadOptions());
count = 0;
for (iter->SeekToLast(); iter->Valid(); iter->Prev()) {
ASSERT_OK(iter->status());
count++;
}
ASSERT_EQ(count, 3);
delete iter;
skip_count += 8; // Same as above, but in reverse order
ASSERT_EQ(skip_count, TestGetTickerCount(options, NUMBER_ITER_SKIP));
ASSERT_OK(Put("aa", "1"));
ASSERT_OK(Put("ab", "1"));
ASSERT_OK(Put("ac", "1"));
ASSERT_OK(Put("ad", "1"));
ASSERT_OK(Flush());
ASSERT_OK(Delete("ab"));
ASSERT_OK(Delete("ac"));
ASSERT_OK(Delete("ad"));
ReadOptions ro;
Slice prefix("b");
ro.iterate_upper_bound = &prefix;
iter = NewIterator(ro);
count = 0;
for(iter->Seek("aa"); iter->Valid(); iter->Next()) {
ASSERT_OK(iter->status());
count++;
}
ASSERT_EQ(count, 1);
delete iter;
skip_count += 6; // 3 deletes + 3 original keys
ASSERT_EQ(skip_count, TestGetTickerCount(options, NUMBER_ITER_SKIP));
iter = NewIterator(ro);
count = 0;
for(iter->SeekToLast(); iter->Valid(); iter->Prev()) {
ASSERT_OK(iter->status());
count++;
}
ASSERT_EQ(count, 2);
delete iter;
// 3 deletes + 3 original keys + lower sequence of "a"
skip_count += 7;
ASSERT_EQ(skip_count, TestGetTickerCount(options, NUMBER_ITER_SKIP));
}
TEST_P(DBIteratorTest, SeekAfterHittingManyInternalKeys) {
Options options = CurrentOptions();
DestroyAndReopen(options);
ReadOptions ropts;
ropts.max_skippable_internal_keys = 2;
ASSERT_OK(Put("1", "val_1"));
// Add more tombstones than max_skippable_internal_keys so that Next() fails.
ASSERT_OK(Delete("2"));
ASSERT_OK(Delete("3"));
ASSERT_OK(Delete("4"));
ASSERT_OK(Delete("5"));
ASSERT_OK(Put("6", "val_6"));
std::unique_ptr<Iterator> iter(NewIterator(ropts));
iter->SeekToFirst();
ASSERT_TRUE(iter->Valid());
ASSERT_EQ(iter->key().ToString(), "1");
ASSERT_EQ(iter->value().ToString(), "val_1");
// This should fail as incomplete due to too many non-visible internal keys on
// the way to the next valid user key.
iter->Next();
ASSERT_TRUE(!iter->Valid());
ASSERT_TRUE(iter->status().IsIncomplete());
// Get the internal key at which Next() failed.
std::string prop_value;
ASSERT_OK(iter->GetProperty("rocksdb.iterator.internal-key", &prop_value));
ASSERT_EQ("4", prop_value);
// Create a new iterator to seek to the internal key.
std::unique_ptr<Iterator> iter2(NewIterator(ropts));
iter2->Seek(prop_value);
ASSERT_TRUE(iter2->Valid());
ASSERT_OK(iter2->status());
ASSERT_EQ(iter2->key().ToString(), "6");
ASSERT_EQ(iter2->value().ToString(), "val_6");
}
// Reproduces a former bug where iterator would skip some records when DBIter
// re-seeks subiterator with Incomplete status.
TEST_P(DBIteratorTest, NonBlockingIterationBugRepro) {
Options options = CurrentOptions();
BlockBasedTableOptions table_options;
// Make sure the sst file has more than one block.
table_options.flush_block_policy_factory =
std::make_shared<FlushBlockEveryKeyPolicyFactory>();
options.table_factory.reset(NewBlockBasedTableFactory(table_options));
DestroyAndReopen(options);
// Two records in sst file, each in its own block.
ASSERT_OK(Put("b", ""));
ASSERT_OK(Put("d", ""));
ASSERT_OK(Flush());
// Create a nonblocking iterator before writing to memtable.
ReadOptions ropt;
ropt.read_tier = kBlockCacheTier;
std::unique_ptr<Iterator> iter(NewIterator(ropt));
// Overwrite a key in memtable many times to hit
// max_sequential_skip_in_iterations (which is 8 by default).
for (int i = 0; i < 20; ++i) {
ASSERT_OK(Put("c", ""));
}
// Load the second block in sst file into the block cache.
{
std::unique_ptr<Iterator> iter2(NewIterator(ReadOptions()));
iter2->Seek("d");
}
// Finally seek the nonblocking iterator.
iter->Seek("a");
// With the bug, the status used to be OK, and the iterator used to point to
// "d".
EXPECT_TRUE(iter->status().IsIncomplete());
}
TEST_P(DBIteratorTest, SeekBackwardAfterOutOfUpperBound) {
ASSERT_OK(Put("a", ""));
ASSERT_OK(Put("b", ""));
ASSERT_OK(Flush());
ReadOptions ropt;
Slice ub = "b";
ropt.iterate_upper_bound = &ub;
std::unique_ptr<Iterator> it(dbfull()->NewIterator(ropt));
it->SeekForPrev("a");
ASSERT_TRUE(it->Valid());
ASSERT_OK(it->status());
ASSERT_EQ("a", it->key().ToString());
it->Next();
ASSERT_FALSE(it->Valid());
ASSERT_OK(it->status());
it->SeekForPrev("a");
ASSERT_OK(it->status());
ASSERT_TRUE(it->Valid());
ASSERT_EQ("a", it->key().ToString());
}
TEST_P(DBIteratorTest, AvoidReseekLevelIterator) {
Options options = CurrentOptions();
options.compression = CompressionType::kNoCompression;
BlockBasedTableOptions table_options;
table_options.block_size = 800;
options.table_factory.reset(NewBlockBasedTableFactory(table_options));
Reopen(options);
Random rnd(301);
std::string random_str = rnd.RandomString(180);
ASSERT_OK(Put("1", random_str));
ASSERT_OK(Put("2", random_str));
ASSERT_OK(Put("3", random_str));
ASSERT_OK(Put("4", random_str));
// A new block
ASSERT_OK(Put("5", random_str));
ASSERT_OK(Put("6", random_str));
ASSERT_OK(Put("7", random_str));
ASSERT_OK(Flush());
ASSERT_OK(Put("8", random_str));
ASSERT_OK(Put("9", random_str));
ASSERT_OK(Flush());
ASSERT_OK(db_->CompactRange(CompactRangeOptions(), nullptr, nullptr));
int num_find_file_in_level = 0;
int num_idx_blk_seek = 0;
SyncPoint::GetInstance()->SetCallBack(
"LevelIterator::Seek:BeforeFindFile",
[&](void* /*arg*/) { num_find_file_in_level++; });
SyncPoint::GetInstance()->SetCallBack(
"IndexBlockIter::Seek:0", [&](void* /*arg*/) { num_idx_blk_seek++; });
SyncPoint::GetInstance()->EnableProcessing();
{
std::unique_ptr<Iterator> iter(NewIterator(ReadOptions()));
iter->Seek("1");
ASSERT_TRUE(iter->Valid());
ASSERT_EQ(1, num_find_file_in_level);
ASSERT_EQ(1, num_idx_blk_seek);
iter->Seek("2");
ASSERT_TRUE(iter->Valid());
ASSERT_EQ(1, num_find_file_in_level);
ASSERT_EQ(1, num_idx_blk_seek);
iter->Seek("3");
ASSERT_TRUE(iter->Valid());
ASSERT_EQ(1, num_find_file_in_level);
ASSERT_EQ(1, num_idx_blk_seek);
iter->Next();
ASSERT_TRUE(iter->Valid());
ASSERT_EQ(1, num_find_file_in_level);
ASSERT_EQ(1, num_idx_blk_seek);
iter->Seek("5");
ASSERT_TRUE(iter->Valid());
ASSERT_EQ(1, num_find_file_in_level);
ASSERT_EQ(2, num_idx_blk_seek);
iter->Seek("6");
ASSERT_TRUE(iter->Valid());
ASSERT_EQ(1, num_find_file_in_level);
ASSERT_EQ(2, num_idx_blk_seek);
iter->Seek("7");
ASSERT_TRUE(iter->Valid());
ASSERT_EQ(1, num_find_file_in_level);
ASSERT_EQ(3, num_idx_blk_seek);
iter->Seek("8");
ASSERT_TRUE(iter->Valid());
ASSERT_EQ(2, num_find_file_in_level);
// Still re-seek because "8" is the boundary key, which has
// the same user key as the seek key.
ASSERT_EQ(4, num_idx_blk_seek);
iter->Seek("5");
ASSERT_TRUE(iter->Valid());
ASSERT_EQ(3, num_find_file_in_level);
ASSERT_EQ(5, num_idx_blk_seek);
iter->Next();
ASSERT_TRUE(iter->Valid());
ASSERT_EQ(3, num_find_file_in_level);
ASSERT_EQ(5, num_idx_blk_seek);
// Seek backward never triggers the index block seek to be skipped
iter->Seek("5");
ASSERT_TRUE(iter->Valid());
ASSERT_EQ(3, num_find_file_in_level);
ASSERT_EQ(6, num_idx_blk_seek);
}
SyncPoint::GetInstance()->DisableProcessing();
}
// MyRocks may change iterate bounds before seek. Simply test to make sure such
// usage doesn't break iterator.
TEST_P(DBIteratorTest, IterateBoundChangedBeforeSeek) {
Options options = CurrentOptions();
options.compression = CompressionType::kNoCompression;
BlockBasedTableOptions table_options;
table_options.block_size = 100;
options.table_factory.reset(NewBlockBasedTableFactory(table_options));
std::string value(50, 'v');
Reopen(options);
ASSERT_OK(Put("aaa", value));
ASSERT_OK(Flush());
ASSERT_OK(Put("bbb", "v"));
ASSERT_OK(Put("ccc", "v"));
ASSERT_OK(Put("ddd", "v"));
ASSERT_OK(Flush());
ASSERT_OK(Put("eee", "v"));
ASSERT_OK(Flush());
ASSERT_OK(db_->CompactRange(CompactRangeOptions(), nullptr, nullptr));
std::string ub1 = "e";
std::string ub2 = "c";
Slice ub(ub1);
ReadOptions read_opts1;
read_opts1.iterate_upper_bound = &ub;
Iterator* iter = NewIterator(read_opts1);
// Seek and iterate accross block boundary.
iter->Seek("b");
ASSERT_TRUE(iter->Valid());
ASSERT_OK(iter->status());
ASSERT_EQ("bbb", iter->key());
ub = Slice(ub2);
iter->Seek("b");
ASSERT_TRUE(iter->Valid());
ASSERT_OK(iter->status());
ASSERT_EQ("bbb", iter->key());
iter->Next();
ASSERT_FALSE(iter->Valid());
ASSERT_OK(iter->status());
delete iter;
std::string lb1 = "a";
std::string lb2 = "c";
Slice lb(lb1);
ReadOptions read_opts2;
read_opts2.iterate_lower_bound = &lb;
iter = NewIterator(read_opts2);
iter->SeekForPrev("d");
ASSERT_TRUE(iter->Valid());
ASSERT_OK(iter->status());
ASSERT_EQ("ccc", iter->key());
lb = Slice(lb2);
iter->SeekForPrev("d");
ASSERT_TRUE(iter->Valid());
ASSERT_OK(iter->status());
ASSERT_EQ("ccc", iter->key());
iter->Prev();
ASSERT_FALSE(iter->Valid());
ASSERT_OK(iter->status());
delete iter;
}
TEST_P(DBIteratorTest, IterateWithLowerBoundAcrossFileBoundary) {
ASSERT_OK(Put("aaa", "v"));
ASSERT_OK(Put("bbb", "v"));
ASSERT_OK(Flush());
ASSERT_OK(Put("ccc", "v"));
ASSERT_OK(Put("ddd", "v"));
ASSERT_OK(Flush());
// Move both files to bottom level.
ASSERT_OK(dbfull()->CompactRange(CompactRangeOptions(), nullptr, nullptr));
Slice lower_bound("b");
ReadOptions read_opts;
read_opts.iterate_lower_bound = &lower_bound;
std::unique_ptr<Iterator> iter(NewIterator(read_opts));
iter->SeekForPrev("d");
ASSERT_TRUE(iter->Valid());
ASSERT_OK(iter->status());
ASSERT_EQ("ccc", iter->key());
iter->Prev();
ASSERT_TRUE(iter->Valid());
ASSERT_OK(iter->status());
ASSERT_EQ("bbb", iter->key());
iter->Prev();
ASSERT_FALSE(iter->Valid());
ASSERT_OK(iter->status());
}
TEST_P(DBIteratorTest, Blob) {
Options options = CurrentOptions();
options.enable_blob_files = true;
options.max_sequential_skip_in_iterations = 2;
options.statistics = CreateDBStatistics();
Reopen(options);
// Note: we have 4 KVs (3 of which are hidden) for key "b" and
// max_sequential_skip_in_iterations is set to 2. Thus, we need to do a reseek
// anytime we move from "b" to "c" or vice versa.
ASSERT_OK(Put("a", "va"));
ASSERT_OK(Flush());
ASSERT_OK(Put("b", "vb0"));
ASSERT_OK(Flush());
ASSERT_OK(Put("b", "vb1"));
ASSERT_OK(Flush());
ASSERT_OK(Put("b", "vb2"));
ASSERT_OK(Flush());
ASSERT_OK(Put("b", "vb3"));
ASSERT_OK(Flush());
ASSERT_OK(Put("c", "vc"));
ASSERT_OK(Flush());
std::unique_ptr<Iterator> iter_guard(NewIterator(ReadOptions()));
Iterator* const iter = iter_guard.get();
iter->SeekToFirst();
ASSERT_EQ(TestGetTickerCount(options, NUMBER_OF_RESEEKS_IN_ITERATION), 0);
ASSERT_EQ(IterStatus(iter), "a->va");
iter->Next();
ASSERT_EQ(TestGetTickerCount(options, NUMBER_OF_RESEEKS_IN_ITERATION), 0);
ASSERT_EQ(IterStatus(iter), "b->vb3");
iter->Next();
ASSERT_EQ(TestGetTickerCount(options, NUMBER_OF_RESEEKS_IN_ITERATION), 1);
ASSERT_EQ(IterStatus(iter), "c->vc");
iter->Next();
ASSERT_EQ(TestGetTickerCount(options, NUMBER_OF_RESEEKS_IN_ITERATION), 1);
ASSERT_EQ(IterStatus(iter), "(invalid)");
iter->SeekToFirst();
ASSERT_EQ(TestGetTickerCount(options, NUMBER_OF_RESEEKS_IN_ITERATION), 1);
ASSERT_EQ(IterStatus(iter), "a->va");
iter->Prev();
ASSERT_EQ(TestGetTickerCount(options, NUMBER_OF_RESEEKS_IN_ITERATION), 1);
ASSERT_EQ(IterStatus(iter), "(invalid)");
iter->SeekToLast();
ASSERT_EQ(TestGetTickerCount(options, NUMBER_OF_RESEEKS_IN_ITERATION), 1);
ASSERT_EQ(IterStatus(iter), "c->vc");
iter->Prev();
ASSERT_EQ(TestGetTickerCount(options, NUMBER_OF_RESEEKS_IN_ITERATION), 2);
ASSERT_EQ(IterStatus(iter), "b->vb3");
iter->Prev();
ASSERT_EQ(TestGetTickerCount(options, NUMBER_OF_RESEEKS_IN_ITERATION), 2);
ASSERT_EQ(IterStatus(iter), "a->va");
iter->Prev();
ASSERT_EQ(TestGetTickerCount(options, NUMBER_OF_RESEEKS_IN_ITERATION), 2);
ASSERT_EQ(IterStatus(iter), "(invalid)");
iter->SeekToLast();
ASSERT_EQ(TestGetTickerCount(options, NUMBER_OF_RESEEKS_IN_ITERATION), 2);
ASSERT_EQ(IterStatus(iter), "c->vc");
iter->Next();
ASSERT_EQ(TestGetTickerCount(options, NUMBER_OF_RESEEKS_IN_ITERATION), 2);
ASSERT_EQ(IterStatus(iter), "(invalid)");
iter->Seek("");
ASSERT_EQ(TestGetTickerCount(options, NUMBER_OF_RESEEKS_IN_ITERATION), 2);
ASSERT_EQ(IterStatus(iter), "a->va");
iter->Seek("a");
ASSERT_EQ(TestGetTickerCount(options, NUMBER_OF_RESEEKS_IN_ITERATION), 2);
ASSERT_EQ(IterStatus(iter), "a->va");
iter->Seek("ax");
ASSERT_EQ(TestGetTickerCount(options, NUMBER_OF_RESEEKS_IN_ITERATION), 2);
ASSERT_EQ(IterStatus(iter), "b->vb3");
iter->SeekForPrev("d");
ASSERT_EQ(TestGetTickerCount(options, NUMBER_OF_RESEEKS_IN_ITERATION), 2);
ASSERT_EQ(IterStatus(iter), "c->vc");
iter->SeekForPrev("c");
ASSERT_EQ(TestGetTickerCount(options, NUMBER_OF_RESEEKS_IN_ITERATION), 2);
ASSERT_EQ(IterStatus(iter), "c->vc");
iter->SeekForPrev("bx");
ASSERT_EQ(TestGetTickerCount(options, NUMBER_OF_RESEEKS_IN_ITERATION), 3);
ASSERT_EQ(IterStatus(iter), "b->vb3");
iter->Seek("b");
ASSERT_EQ(TestGetTickerCount(options, NUMBER_OF_RESEEKS_IN_ITERATION), 3);
ASSERT_EQ(IterStatus(iter), "b->vb3");
iter->Seek("z");
ASSERT_EQ(TestGetTickerCount(options, NUMBER_OF_RESEEKS_IN_ITERATION), 3);
ASSERT_EQ(IterStatus(iter), "(invalid)");
iter->SeekForPrev("b");
ASSERT_EQ(TestGetTickerCount(options, NUMBER_OF_RESEEKS_IN_ITERATION), 4);
ASSERT_EQ(IterStatus(iter), "b->vb3");
iter->SeekForPrev("");
ASSERT_EQ(TestGetTickerCount(options, NUMBER_OF_RESEEKS_IN_ITERATION), 4);
ASSERT_EQ(IterStatus(iter), "(invalid)");
// Switch from reverse to forward
iter->SeekToLast();
ASSERT_EQ(TestGetTickerCount(options, NUMBER_OF_RESEEKS_IN_ITERATION), 4);
iter->Prev();
ASSERT_EQ(TestGetTickerCount(options, NUMBER_OF_RESEEKS_IN_ITERATION), 5);
iter->Prev();
ASSERT_EQ(TestGetTickerCount(options, NUMBER_OF_RESEEKS_IN_ITERATION), 5);
iter->Next();
ASSERT_EQ(TestGetTickerCount(options, NUMBER_OF_RESEEKS_IN_ITERATION), 6);
ASSERT_EQ(IterStatus(iter), "b->vb3");
// Switch from forward to reverse
iter->SeekToFirst();
ASSERT_EQ(TestGetTickerCount(options, NUMBER_OF_RESEEKS_IN_ITERATION), 6);
iter->Next();
ASSERT_EQ(TestGetTickerCount(options, NUMBER_OF_RESEEKS_IN_ITERATION), 6);
iter->Next();
ASSERT_EQ(TestGetTickerCount(options, NUMBER_OF_RESEEKS_IN_ITERATION), 7);
iter->Prev();
ASSERT_EQ(TestGetTickerCount(options, NUMBER_OF_RESEEKS_IN_ITERATION), 8);
ASSERT_EQ(IterStatus(iter), "b->vb3");
}
INSTANTIATE_TEST_CASE_P(DBIteratorTestInstance, DBIteratorTest,
testing::Values(true, false));
// Tests how DBIter work with ReadCallback
class DBIteratorWithReadCallbackTest : public DBIteratorTest {};
TEST_F(DBIteratorWithReadCallbackTest, ReadCallback) {
class TestReadCallback : public ReadCallback {
public:
explicit TestReadCallback(SequenceNumber _max_visible_seq)
: ReadCallback(_max_visible_seq) {}
bool IsVisibleFullCheck(SequenceNumber seq) override {
return seq <= max_visible_seq_;
}
};
ASSERT_OK(Put("foo", "v1"));
ASSERT_OK(Put("foo", "v2"));
ASSERT_OK(Put("foo", "v3"));
ASSERT_OK(Put("a", "va"));
ASSERT_OK(Put("z", "vz"));
SequenceNumber seq1 = db_->GetLatestSequenceNumber();
TestReadCallback callback1(seq1);
ASSERT_OK(Put("foo", "v4"));
ASSERT_OK(Put("foo", "v5"));
ASSERT_OK(Put("bar", "v7"));
SequenceNumber seq2 = db_->GetLatestSequenceNumber();
auto* cfd =
static_cast_with_check<ColumnFamilyHandleImpl>(db_->DefaultColumnFamily())
->cfd();
// The iterator are suppose to see data before seq1.
Iterator* iter =
dbfull()->NewIteratorImpl(ReadOptions(), cfd, seq2, &callback1);
// Seek
// The latest value of "foo" before seq1 is "v3"
iter->Seek("foo");
ASSERT_TRUE(iter->Valid());
ASSERT_OK(iter->status());
ASSERT_EQ("foo", iter->key());
ASSERT_EQ("v3", iter->value());
// "bar" is not visible to the iterator. It will move on to the next key
// "foo".
iter->Seek("bar");
ASSERT_TRUE(iter->Valid());
ASSERT_OK(iter->status());
ASSERT_EQ("foo", iter->key());
ASSERT_EQ("v3", iter->value());
// Next
// Seek to "a"
iter->Seek("a");
ASSERT_TRUE(iter->Valid());
ASSERT_OK(iter->status());
ASSERT_EQ("va", iter->value());
// "bar" is not visible to the iterator. It will move on to the next key
// "foo".
iter->Next();
ASSERT_TRUE(iter->Valid());
ASSERT_OK(iter->status());
ASSERT_EQ("foo", iter->key());
ASSERT_EQ("v3", iter->value());
// Prev
// Seek to "z"
iter->Seek("z");
ASSERT_TRUE(iter->Valid());
ASSERT_OK(iter->status());
ASSERT_EQ("vz", iter->value());
// The previous key is "foo", which is visible to the iterator.
iter->Prev();
ASSERT_TRUE(iter->Valid());
ASSERT_OK(iter->status());
ASSERT_EQ("foo", iter->key());
ASSERT_EQ("v3", iter->value());
// "bar" is not visible to the iterator. It will move on to the next key "a".
iter->Prev(); // skipping "bar"
ASSERT_TRUE(iter->Valid());
ASSERT_OK(iter->status());
ASSERT_EQ("a", iter->key());
ASSERT_EQ("va", iter->value());
// SeekForPrev
// The previous key is "foo", which is visible to the iterator.
iter->SeekForPrev("y");
ASSERT_TRUE(iter->Valid());
ASSERT_OK(iter->status());
ASSERT_EQ("foo", iter->key());
ASSERT_EQ("v3", iter->value());
// "bar" is not visible to the iterator. It will move on to the next key "a".
iter->SeekForPrev("bar");
ASSERT_TRUE(iter->Valid());
ASSERT_OK(iter->status());
ASSERT_EQ("a", iter->key());
ASSERT_EQ("va", iter->value());
delete iter;
// Prev beyond max_sequential_skip_in_iterations
uint64_t num_versions =
CurrentOptions().max_sequential_skip_in_iterations + 10;
for (uint64_t i = 0; i < num_versions; i++) {
ASSERT_OK(Put("bar", ToString(i)));
}
SequenceNumber seq3 = db_->GetLatestSequenceNumber();
TestReadCallback callback2(seq3);
ASSERT_OK(Put("bar", "v8"));
SequenceNumber seq4 = db_->GetLatestSequenceNumber();
// The iterator is suppose to see data before seq3.
iter = dbfull()->NewIteratorImpl(ReadOptions(), cfd, seq4, &callback2);
// Seek to "z", which is visible.
iter->Seek("z");
ASSERT_TRUE(iter->Valid());
ASSERT_OK(iter->status());
ASSERT_EQ("vz", iter->value());
// Previous key is "foo" and the last value "v5" is visible.
iter->Prev();
ASSERT_TRUE(iter->Valid());
ASSERT_OK(iter->status());
ASSERT_EQ("foo", iter->key());
ASSERT_EQ("v5", iter->value());
// Since the number of values of "bar" is more than
// max_sequential_skip_in_iterations, Prev() will ultimately fallback to
// seek in forward direction. Here we test the fallback seek is correct.
// The last visible value should be (num_versions - 1), as "v8" is not
// visible.
iter->Prev();
ASSERT_TRUE(iter->Valid());
ASSERT_OK(iter->status());
ASSERT_EQ("bar", iter->key());
ASSERT_EQ(ToString(num_versions - 1), iter->value());
delete iter;
}
TEST_F(DBIteratorTest, BackwardIterationOnInplaceUpdateMemtable) {
Options options = CurrentOptions();
options.create_if_missing = true;
options.inplace_update_support = false;
options.env = env_;
DestroyAndReopen(options);
constexpr int kNumKeys = 10;
// Write kNumKeys to WAL.
for (int i = 0; i < kNumKeys; ++i) {
ASSERT_OK(Put(Key(i), "val"));
}
ReadOptions read_opts;
read_opts.total_order_seek = true;
{
std::unique_ptr<Iterator> iter(db_->NewIterator(read_opts));
int count = 0;
for (iter->SeekToLast(); iter->Valid(); iter->Prev()) {
++count;
}
ASSERT_EQ(kNumKeys, count);
}
// Reopen and rebuild the memtable from WAL.
options.create_if_missing = false;
options.avoid_flush_during_recovery = true;
options.inplace_update_support = true;
options.allow_concurrent_memtable_write = false;
Reopen(options);
{
std::unique_ptr<Iterator> iter(db_->NewIterator(read_opts));
iter->SeekToLast();
// Backward iteration not supported due to inplace_update_support = true.
ASSERT_TRUE(iter->status().IsNotSupported());
ASSERT_FALSE(iter->Valid());
}
}
} // namespace ROCKSDB_NAMESPACE
int main(int argc, char** argv) {
ROCKSDB_NAMESPACE::port::InstallStackTraceHandler();
::testing::InitGoogleTest(&argc, argv);
return RUN_ALL_TESTS();
}
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