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Relax VersionStorageInfo::GetOverlappingInputs check (#4050)

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Summary:
Do not consider the range tombstone sentinel key as causing 2 adjacent
sstables in a level to overlap. When a range tombstone's end key is the
largest key in an sstable, the sstable's end key is so to a "sentinel"
value that is the smallest key in the next sstable with a sequence
number of kMaxSequenceNumber. This "sentinel" is guaranteed to not
overlap in internal-key space with the next sstable. Unfortunately,
GetOverlappingFiles uses user-keys to determine overlap and was thus
considering 2 adjacent sstables in a level to overlap if they were
separated by this sentinel key. This in turn would cause compactions to
be larger than necessary.

Note that this conflicts with
https://github.com/facebook/rocksdb/pull/2769 and cases
`DBRangeDelTest.CompactionTreatsSplitInputLevelDeletionAtomically` to
fail.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4050

Differential Revision: D8844423

Pulled By: ajkr

fbshipit-source-id: df3f9f1db8f4cff2bff77376b98b83c2ae1d155b
This commit is contained in:
Peter Mattis 2018-07-13 17:34:54 -07:00 committed by Facebook Github Bot
parent 21171615c1
commit 90fc40690a
15 changed files with 396 additions and 152 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
db/builder.cc
View File

@ -204,7 +204,7 @@ Status BuildTable(
// we will regrad this verification as user reads since the goal is
// to cache it here for further user reads
std::unique_ptr<InternalIterator> it(table_cache->NewIterator(
ReadOptions(), env_options, internal_comparator, meta->fd,
ReadOptions(), env_options, internal_comparator, *meta,
nullptr /* range_del_agg */,
mutable_cf_options.prefix_extractor.get(), nullptr,
(internal_stats == nullptr) ? nullptr

2
db/compaction_job.cc
View File

@ -635,7 +635,7 @@ Status CompactionJob::Run() {
// to cache it here for further user reads
InternalIterator* iter = cfd->table_cache()->NewIterator(
ReadOptions(), env_options_, cfd->internal_comparator(),
files_meta[file_idx]->fd, nullptr /* range_del_agg */,
*files_meta[file_idx], nullptr /* range_del_agg */,
prefix_extractor, nullptr,
cfd->internal_stats()->GetFileReadHist(
compact_->compaction->output_level()),

104
db/db_range_del_test.cc
View File

@ -916,11 +916,14 @@ TEST_F(DBRangeDelTest, MemtableBloomFilter) {
}
TEST_F(DBRangeDelTest, CompactionTreatsSplitInputLevelDeletionAtomically) {
// make sure compaction treats files containing a split range deletion in the
// input level as an atomic unit. I.e., compacting any input-level file(s)
// containing a portion of the range deletion causes all other input-level
// files containing portions of that same range deletion to be included in the
// compaction.
// This test originally verified that compaction treated files containing a
// split range deletion in the input level as an atomic unit. I.e.,
// compacting any input-level file(s) containing a portion of the range
// deletion causes all other input-level files containing portions of that
// same range deletion to be included in the compaction. Range deletion
// tombstones are now truncated to sstable boundaries which removed the need
// for that behavior (which could lead to excessively large
// compactions).
const int kNumFilesPerLevel = 4, kValueBytes = 4 << 10;
Options options = CurrentOptions();
options.compression = kNoCompression;
@ -967,22 +970,111 @@ TEST_F(DBRangeDelTest, CompactionTreatsSplitInputLevelDeletionAtomically) {
if (i == 0) {
ASSERT_OK(db_->CompactFiles(
CompactionOptions(), {meta.levels[1].files[0].name}, 2 /* level */));
ASSERT_EQ(0, NumTableFilesAtLevel(1));
} else if (i == 1) {
auto begin_str = Key(0), end_str = Key(1);
Slice begin = begin_str, end = end_str;
ASSERT_OK(db_->CompactRange(CompactRangeOptions(), &begin, &end));
ASSERT_EQ(3, NumTableFilesAtLevel(1));
} else if (i == 2) {
ASSERT_OK(db_->SetOptions(db_->DefaultColumnFamily(),
{{"max_bytes_for_level_base", "10000"}}));
dbfull()->TEST_WaitForCompact();
ASSERT_EQ(1, NumTableFilesAtLevel(1));
}
ASSERT_EQ(0, NumTableFilesAtLevel(1));
ASSERT_GT(NumTableFilesAtLevel(2), 0);
db_->ReleaseSnapshot(snapshot);
}
}
TEST_F(DBRangeDelTest, RangeTombstoneEndKeyAsSstableUpperBound) {
// Test the handling of the range-tombstone end-key as the
// upper-bound for an sstable.
const int kNumFilesPerLevel = 2, kValueBytes = 4 << 10;
Options options = CurrentOptions();
options.compression = kNoCompression;
options.level0_file_num_compaction_trigger = kNumFilesPerLevel;
options.memtable_factory.reset(
new SpecialSkipListFactory(2 /* num_entries_flush */));
options.target_file_size_base = kValueBytes;
options.disable_auto_compactions = true;
DestroyAndReopen(options);
// Create an initial sstable at L2:
// [key000000#1,1, key000000#1,1]
ASSERT_OK(Put(Key(0), ""));
ASSERT_OK(db_->Flush(FlushOptions()));
MoveFilesToLevel(2);
ASSERT_EQ(1, NumTableFilesAtLevel(2));
// A snapshot protects the range tombstone from dropping due to
// becoming obsolete.
const Snapshot* snapshot = db_->GetSnapshot();
db_->DeleteRange(WriteOptions(), db_->DefaultColumnFamily(),
Key(0), Key(2 * kNumFilesPerLevel));
// Create 2 additional sstables in L0. Note that the first sstable
// contains the range tombstone.
// [key000000#3,1, key000004#72057594037927935,15]
// [key000001#5,1, key000002#6,1]
Random rnd(301);
std::string value = RandomString(&rnd, kValueBytes);
for (int j = 0; j < kNumFilesPerLevel; ++j) {
// Give files overlapping key-ranges to prevent a trivial move when we
// compact from L0 to L1.
ASSERT_OK(Put(Key(j), value));
ASSERT_OK(Put(Key(2 * kNumFilesPerLevel - 1 - j), value));
ASSERT_OK(db_->Flush(FlushOptions()));
ASSERT_EQ(j + 1, NumTableFilesAtLevel(0));
}
// Compact the 2 L0 sstables to L1, resulting in the following LSM. There
// are 2 sstables generated in L1 due to the target_file_size_base setting.
// L1:
// [key000000#3,1, key000002#72057594037927935,15]
// [key000002#6,1, key000004#72057594037927935,15]
// L2:
// [key000000#1,1, key000000#1,1]
MoveFilesToLevel(1);
ASSERT_EQ(2, NumTableFilesAtLevel(1));
{
// Compact the second sstable in L1:
// L1:
// [key000000#3,1, key000002#72057594037927935,15]
// L2:
// [key000000#1,1, key000000#1,1]
// [key000002#6,1, key000004#72057594037927935,15]
auto begin_str = Key(3);
const rocksdb::Slice begin = begin_str;
dbfull()->TEST_CompactRange(1, &begin, nullptr);
ASSERT_EQ(1, NumTableFilesAtLevel(1));
ASSERT_EQ(2, NumTableFilesAtLevel(2));
}
{
// Compact the first sstable in L1. This should be copacetic, but
// was previously resulting in overlapping sstables in L2 due to
// mishandling of the range tombstone end-key when used as the
// largest key for an sstable. The resulting LSM structure should
// be:
//
// L2:
// [key000000#1,1, key000001#72057594037927935,15]
// [key000001#5,1, key000002#72057594037927935,15]
// [key000002#6,1, key000004#72057594037927935,15]
auto begin_str = Key(0);
const rocksdb::Slice begin = begin_str;
dbfull()->TEST_CompactRange(1, &begin, &begin);
ASSERT_EQ(0, NumTableFilesAtLevel(1));
ASSERT_EQ(3, NumTableFilesAtLevel(2));
}
db_->ReleaseSnapshot(snapshot);
}
TEST_F(DBRangeDelTest, UnorderedTombstones) {
// Regression test for #2752. Range delete tombstones between
// different snapshot stripes are not stored in order, so the first

16
db/dbformat.h
View File

@ -140,10 +140,14 @@ inline Slice ExtractUserKey(const Slice& internal_key) {
return Slice(internal_key.data(), internal_key.size() - 8);
}
inline ValueType ExtractValueType(const Slice& internal_key) {
inline uint64_t ExtractInternalKeyFooter(const Slice& internal_key) {
assert(internal_key.size() >= 8);
const size_t n = internal_key.size();
uint64_t num = DecodeFixed64(internal_key.data() + n - 8);
return DecodeFixed64(internal_key.data() + n - 8);
}
inline ValueType ExtractValueType(const Slice& internal_key) {
uint64_t num = ExtractInternalKeyFooter(internal_key);
unsigned char c = num & 0xff;
return static_cast<ValueType>(c);
}
@ -606,9 +610,15 @@ struct RangeTombstone {
return InternalKey(start_key_, seq_, kTypeRangeDeletion);
}
// The tombstone end-key is exclusive, so we generate an internal-key here
// which has a similar property. Using kMaxSequenceNumber guarantees that
// the returned internal-key will compare less than any other internal-key
// with the same user-key. This in turn guarantees that the serialized
// end-key for a tombstone such as [a-b] will compare less than the key "b".
//
// be careful to use SerializeEndKey(), allocates new memory
InternalKey SerializeEndKey() const {
return InternalKey(end_key_, seq_, kTypeRangeDeletion);
return InternalKey(end_key_, kMaxSequenceNumber, kTypeRangeDeletion);
}
};

7
db/dbformat_test.cc
View File

@ -192,6 +192,13 @@ TEST_F(FormatTest, UpdateInternalKey) {
ASSERT_EQ(new_val_type, decoded.type);
}
TEST_F(FormatTest, RangeTombstoneSerializeEndKey) {
RangeTombstone t("a", "b", 2);
InternalKey k("b", 3, kTypeValue);
const InternalKeyComparator cmp(BytewiseComparator());
ASSERT_LT(cmp.Compare(t.SerializeEndKey(), k), 0);
}
} // namespace rocksdb
int main(int argc, char** argv) {

8
db/forward_iterator.cc
View File

@ -75,7 +75,7 @@ class ForwardLevelIterator : public InternalIterator {
cfd_->internal_comparator(), {} /* snapshots */);
file_iter_ = cfd_->table_cache()->NewIterator(
read_options_, *(cfd_->soptions()), cfd_->internal_comparator(),
files_[file_index_]->fd,
*files_[file_index_],
read_options_.ignore_range_deletions ? nullptr : &range_del_agg,
prefix_extractor_, nullptr /* table_reader_ptr */, nullptr, false);
file_iter_->SetPinnedItersMgr(pinned_iters_mgr_);
@ -635,7 +635,7 @@ void ForwardIterator::RebuildIterators(bool refresh_sv) {
continue;
}
l0_iters_.push_back(cfd_->table_cache()->NewIterator(
read_options_, *cfd_->soptions(), cfd_->internal_comparator(), l0->fd,
read_options_, *cfd_->soptions(), cfd_->internal_comparator(), *l0,
read_options_.ignore_range_deletions ? nullptr : &range_del_agg,
sv_->mutable_cf_options.prefix_extractor.get()));
}
@ -706,7 +706,7 @@ void ForwardIterator::RenewIterators() {
}
l0_iters_new.push_back(cfd_->table_cache()->NewIterator(
read_options_, *cfd_->soptions(), cfd_->internal_comparator(),
l0_files_new[inew]->fd,
*l0_files_new[inew],
read_options_.ignore_range_deletions ? nullptr : &range_del_agg,
svnew->mutable_cf_options.prefix_extractor.get()));
}
@ -766,7 +766,7 @@ void ForwardIterator::ResetIncompleteIterators() {
DeleteIterator(l0_iters_[i]);
l0_iters_[i] = cfd_->table_cache()->NewIterator(
read_options_, *cfd_->soptions(), cfd_->internal_comparator(),
l0_files[i]->fd, nullptr /* range_del_agg */,
*l0_files[i], nullptr /* range_del_agg */,
sv_->mutable_cf_options.prefix_extractor.get());
l0_iters_[i]->SetPinnedItersMgr(pinned_iters_mgr_);
}

27
db/range_del_aggregator.cc
View File

@ -426,7 +426,9 @@ bool RangeDelAggregator::IsRangeOverlapped(const Slice& start,
}
Status RangeDelAggregator::AddTombstones(
std::unique_ptr<InternalIterator> input) {
std::unique_ptr<InternalIterator> input,
const InternalKey* smallest,
const InternalKey* largest) {
if (input == nullptr) {
return Status::OK();
}
@ -450,6 +452,29 @@ Status RangeDelAggregator::AddTombstones(
return Status::Corruption("Unable to parse range tombstone InternalKey");
}
RangeTombstone tombstone(parsed_key, input->value());
// Truncate the tombstone to the range [smallest, largest].
if (smallest != nullptr) {
if (icmp_.user_comparator()->Compare(
tombstone.start_key_, smallest->user_key()) < 0) {
tombstone.start_key_ = smallest->user_key();
}
}
if (largest != nullptr) {
// This is subtly correct despite the discrepancy between
// FileMetaData::largest being inclusive while RangeTombstone::end_key_
// is exclusive. A tombstone will only extend past the bounds of an
// sstable if its end-key is the largest key in the table. If that
// occurs, the largest key for the table is set based on the smallest
// key in the next table in the level. In that case, largest->user_key()
// is not actually a key in the current table and thus we can use it as
// the exclusive end-key for the tombstone.
if (icmp_.user_comparator()->Compare(
tombstone.end_key_, largest->user_key()) > 0) {
// The largest key should be a tombstone sentinel key.
assert(GetInternalKeySeqno(largest->Encode()) == kMaxSequenceNumber);
tombstone.end_key_ = largest->user_key();
}
}
GetRangeDelMap(tombstone.seq_).AddTombstone(std::move(tombstone));
input->Next();
}

10
db/range_del_aggregator.h
View File

@ -137,9 +137,15 @@ class RangeDelAggregator {
bool IsRangeOverlapped(const Slice& start, const Slice& end);
// Adds tombstones to the tombstone aggregation structure maintained by this
// object.
// object. Tombstones are truncated to smallest and largest. If smallest (or
// largest) is null, it is not used for truncation. When adding range
// tombstones present in an sstable, smallest and largest should be set to
// the smallest and largest keys from the sstable file metadata. Note that
// tombstones end keys are exclusive while largest is inclusive.
// @return non-OK status if any of the tombstone keys are corrupted.
Status AddTombstones(std::unique_ptr<InternalIterator> input);
Status AddTombstones(std::unique_ptr<InternalIterator> input,
const InternalKey* smallest = nullptr,
const InternalKey* largest = nullptr);
// Resets iterators maintained across calls to ShouldDelete(). This may be
// called when the tombstones change, or the owner may call explicitly, e.g.,

43
db/range_del_aggregator_test.cc
View File

@ -19,6 +19,7 @@ namespace {
struct ExpectedPoint {
Slice begin;
SequenceNumber seq;
bool expectAlive;
};
enum Direction {
@ -29,7 +30,9 @@ enum Direction {
static auto icmp = InternalKeyComparator(BytewiseComparator());
void AddTombstones(RangeDelAggregator* range_del_agg,
const std::vector<RangeTombstone>& range_dels) {
const std::vector<RangeTombstone>& range_dels,
const InternalKey* smallest = nullptr,
const InternalKey* largest = nullptr) {
std::vector<std::string> keys, values;
for (const auto& range_del : range_dels) {
auto key_and_value = range_del.Serialize();
@ -38,7 +41,7 @@ void AddTombstones(RangeDelAggregator* range_del_agg,
}
std::unique_ptr<test::VectorIterator> range_del_iter(
new test::VectorIterator(keys, values));
range_del_agg->AddTombstones(std::move(range_del_iter));
range_del_agg->AddTombstones(std::move(range_del_iter), smallest, largest);
}
void VerifyTombstonesEq(const RangeTombstone& a, const RangeTombstone& b) {
@ -62,7 +65,9 @@ void VerifyRangeDelIter(
void VerifyRangeDels(
const std::vector<RangeTombstone>& range_dels_in,
const std::vector<ExpectedPoint>& expected_points,
const std::vector<RangeTombstone>& expected_collapsed_range_dels) {
const std::vector<RangeTombstone>& expected_collapsed_range_dels,
const InternalKey* smallest = nullptr,
const InternalKey* largest = nullptr) {
// Test same result regardless of which order the range deletions are added
// and regardless of collapsed mode.
for (bool collapsed : {false, true}) {
@ -73,7 +78,7 @@ void VerifyRangeDels(
if (dir == kReverse) {
std::reverse(range_dels.begin(), range_dels.end());
}
AddTombstones(&range_del_agg, range_dels);
AddTombstones(&range_del_agg, range_dels, smallest, largest);
auto mode = RangeDelPositioningMode::kFullScan;
if (collapsed) {
@ -88,22 +93,29 @@ void VerifyRangeDels(
ASSERT_FALSE(range_del_agg.ShouldDelete(parsed_key, mode));
if (parsed_key.sequence > 0) {
--parsed_key.sequence;
ASSERT_TRUE(range_del_agg.ShouldDelete(parsed_key, mode));
if (expected_point.expectAlive) {
ASSERT_FALSE(range_del_agg.ShouldDelete(parsed_key, mode));
} else {
ASSERT_TRUE(range_del_agg.ShouldDelete(parsed_key, mode));
}
}
}
if (collapsed) {
range_dels = expected_collapsed_range_dels;
} else {
// Tombstones in an uncollapsed map are presented in start key order.
// Tombstones with the same start key are presented in insertion order.
VerifyRangeDelIter(range_del_agg.NewIterator().get(), range_dels);
} else if (smallest == nullptr && largest == nullptr) {
// Tombstones in an uncollapsed map are presented in start key
// order. Tombstones with the same start key are presented in
// insertion order. We don't handle tombstone truncation here, so the
// verification is only performed if no truncation was requested.
std::stable_sort(range_dels.begin(), range_dels.end(),
[&](const RangeTombstone& a, const RangeTombstone& b) {
return icmp.user_comparator()->Compare(
a.start_key_, b.start_key_) < 0;
});
VerifyRangeDelIter(range_del_agg.NewIterator().get(), range_dels);
}
VerifyRangeDelIter(range_del_agg.NewIterator().get(), range_dels);
}
}
@ -275,6 +287,19 @@ TEST_F(RangeDelAggregatorTest, MergingIteratorSeek) {
{{"c", "d", 20}, {"e", "f", 20}, {"f", "g", 10}});
}
TEST_F(RangeDelAggregatorTest, TruncateTombstones) {
const InternalKey smallest("b", 1, kTypeRangeDeletion);
const InternalKey largest("e", kMaxSequenceNumber, kTypeRangeDeletion);
VerifyRangeDels(
{{"a", "c", 10}, {"d", "f", 10}},
{{"a", 10, true}, // truncated
{"b", 10, false}, // not truncated
{"d", 10, false}, // not truncated
{"e", 10, true}}, // truncated
{{"b", "c", 10}, {"d", "e", 10}},
&smallest, &largest);
}
} // namespace rocksdb
int main(int argc, char** argv) {

2
db/repair.cc
View File

@ -500,7 +500,7 @@ class Repairer {
}
if (status.ok()) {
InternalIterator* iter = table_cache_->NewIterator(
ReadOptions(), env_options_, cfd->internal_comparator(), t->meta.fd,
ReadOptions(), env_options_, cfd->internal_comparator(), t->meta,
nullptr /* range_del_agg */,
cfd->GetLatestMutableCFOptions()->prefix_extractor.get());
bool empty = true;

53
db/table_cache.cc
View File

@ -180,7 +180,7 @@ Status TableCache::FindTable(const EnvOptions& env_options,
InternalIterator* TableCache::NewIterator(
const ReadOptions& options, const EnvOptions& env_options,
const InternalKeyComparator& icomparator, const FileDescriptor& fd,
const InternalKeyComparator& icomparator, const FileMetaData& file_meta,
RangeDelAggregator* range_del_agg, const SliceTransform* prefix_extractor,
TableReader** table_reader_ptr, HistogramImpl* file_read_hist,
bool for_compaction, Arena* arena, bool skip_filters, int level) {
@ -211,6 +211,7 @@ InternalIterator* TableCache::NewIterator(
create_new_table_reader = readahead > 0;
}
auto& fd = file_meta.fd;
if (create_new_table_reader) {
unique_ptr<TableReader> table_reader_unique_ptr;
s = GetTableReader(
@ -265,7 +266,10 @@ InternalIterator* TableCache::NewIterator(
s = range_del_iter->status();
}
if (s.ok()) {
s = range_del_agg->AddTombstones(std::move(range_del_iter));
s = range_del_agg->AddTombstones(
std::move(range_del_iter),
&file_meta.smallest,
&file_meta.largest);
}
}
}
@ -280,51 +284,14 @@ InternalIterator* TableCache::NewIterator(
return result;
}
InternalIterator* TableCache::NewRangeTombstoneIterator(
const ReadOptions& options, const EnvOptions& env_options,
const InternalKeyComparator& icomparator, const FileDescriptor& fd,
HistogramImpl* file_read_hist, bool skip_filters, int level,
const SliceTransform* prefix_extractor) {
Status s;
Cache::Handle* handle = nullptr;
TableReader* table_reader = fd.table_reader;
if (table_reader == nullptr) {
s = FindTable(env_options, icomparator, fd, &handle, prefix_extractor,
options.read_tier == kBlockCacheTier /* no_io */,
true /* record read_stats */, file_read_hist, skip_filters,
level);
if (s.ok()) {
table_reader = GetTableReaderFromHandle(handle);
}
}
InternalIterator* result = nullptr;
if (s.ok()) {
result = table_reader->NewRangeTombstoneIterator(options);
if (result != nullptr) {
if (handle != nullptr) {
result->RegisterCleanup(&UnrefEntry, cache_, handle);
}
}
}
if (result == nullptr && handle != nullptr) {
// the range deletion block didn't exist, or there was a failure between
// getting handle and getting iterator.
ReleaseHandle(handle);
}
if (!s.ok()) {
assert(result == nullptr);
result = NewErrorInternalIterator(s);
}
return result;
}
Status TableCache::Get(const ReadOptions& options,
const InternalKeyComparator& internal_comparator,
const FileDescriptor& fd, const Slice& k,
const FileMetaData& file_meta, const Slice& k,
GetContext* get_context,
const SliceTransform* prefix_extractor,
HistogramImpl* file_read_hist, bool skip_filters,
int level) {
auto& fd = file_meta.fd;
std::string* row_cache_entry = nullptr;
bool done = false;
#ifndef ROCKSDB_LITE
@ -405,7 +372,9 @@ Status TableCache::Get(const ReadOptions& options,
}
if (s.ok()) {
s = get_context->range_del_agg()->AddTombstones(
std::move(range_del_iter));
std::move(range_del_iter),
&file_meta.smallest,
&file_meta.largest);
}
}
if (s.ok()) {

11
db/table_cache.h
View File

@ -53,19 +53,12 @@ class TableCache {
InternalIterator* NewIterator(
const ReadOptions& options, const EnvOptions& toptions,
const InternalKeyComparator& internal_comparator,
const FileDescriptor& file_fd, RangeDelAggregator* range_del_agg,
const FileMetaData& file_meta, RangeDelAggregator* range_del_agg,
const SliceTransform* prefix_extractor = nullptr,
TableReader** table_reader_ptr = nullptr,
HistogramImpl* file_read_hist = nullptr, bool for_compaction = false,
Arena* arena = nullptr, bool skip_filters = false, int level = -1);
InternalIterator* NewRangeTombstoneIterator(
const ReadOptions& options, const EnvOptions& toptions,
const InternalKeyComparator& internal_comparator,
const FileDescriptor& file_fd, HistogramImpl* file_read_hist,
bool skip_filters, int level,
const SliceTransform* prefix_extractor = nullptr);
// If a seek to internal key "k" in specified file finds an entry,
// call (*handle_result)(arg, found_key, found_value) repeatedly until
// it returns false.
@ -76,7 +69,7 @@ class TableCache {
// @param level The level this table is at, -1 for "not set / don't know"
Status Get(const ReadOptions& options,
const InternalKeyComparator& internal_comparator,
const FileDescriptor& file_fd, const Slice& k,
const FileMetaData& file_meta, const Slice& k,
GetContext* get_context,
const SliceTransform* prefix_extractor = nullptr,
HistogramImpl* file_read_hist = nullptr, bool skip_filters = false,

175
db/version_set.cc
View File

@ -548,8 +548,9 @@ class LevelIterator final : public InternalIterator {
}
return table_cache_->NewIterator(
read_options_, env_options_, icomparator_, file_meta.fd, range_del_agg_,
prefix_extractor_, nullptr /* don't need reference to table */,
read_options_, env_options_, icomparator_, *file_meta.file_metadata,
range_del_agg_, prefix_extractor_,
nullptr /* don't need reference to table */,
file_read_hist_, for_compaction_, nullptr /* arena */, skip_filters_,
level_);
}
@ -1000,7 +1001,7 @@ void Version::AddIteratorsForLevel(const ReadOptions& read_options,
for (size_t i = 0; i < storage_info_.LevelFilesBrief(0).num_files; i++) {
const auto& file = storage_info_.LevelFilesBrief(0).files[i];
merge_iter_builder->AddIterator(cfd_->table_cache()->NewIterator(
read_options, soptions, cfd_->internal_comparator(), file.fd,
read_options, soptions, cfd_->internal_comparator(), *file.file_metadata,
range_del_agg, mutable_cf_options_.prefix_extractor.get(), nullptr,
cfd_->internal_stats()->GetFileReadHist(0), false, arena,
false /* skip_filters */, 0 /* level */));
@ -1053,7 +1054,7 @@ Status Version::OverlapWithLevelIterator(const ReadOptions& read_options,
continue;
}
ScopedArenaIterator iter(cfd_->table_cache()->NewIterator(
read_options, env_options, cfd_->internal_comparator(), file->fd,
read_options, env_options, cfd_->internal_comparator(), *file->file_metadata,
&range_del_agg, mutable_cf_options_.prefix_extractor.get(), nullptr,
cfd_->internal_stats()->GetFileReadHist(0), false, &arena,
false /* skip_filters */, 0 /* level */));
@ -1198,8 +1199,8 @@ void Version::Get(const ReadOptions& read_options, const LookupKey& k,
}
*status = table_cache_->Get(
read_options, *internal_comparator(), f->fd, ikey, &get_context,
mutable_cf_options_.prefix_extractor.get(),
read_options, *internal_comparator(), *f->file_metadata, ikey,
&get_context, mutable_cf_options_.prefix_extractor.get(),
cfd_->internal_stats()->GetFileReadHist(fp.GetHitFileLevel()),
IsFilterSkipped(static_cast<int>(fp.GetHitFileLevel()),
fp.IsHitFileLastInLevel()),
@ -2053,8 +2054,8 @@ void VersionStorageInfo::GetOverlappingInputs(
*file_index = -1;
}
const Comparator* user_cmp = user_comparator_;
if (begin != nullptr && end != nullptr && level > 0) {
GetOverlappingInputsRangeBinarySearch(level, user_begin, user_end, inputs,
if (level > 0) {
GetOverlappingInputsRangeBinarySearch(level, begin, end, inputs,
hint_index, file_index);
return;
}
@ -2109,24 +2110,73 @@ void VersionStorageInfo::GetCleanInputsWithinInterval(
return;
}
Slice user_begin, user_end;
const auto& level_files = level_files_brief_[level];
if (begin == nullptr) {
user_begin = ExtractUserKey(level_files.files[0].smallest_key);
} else {
user_begin = begin->user_key();
begin = &level_files.files[0].file_metadata->smallest;
}
if (end == nullptr) {
user_end = ExtractUserKey(
level_files.files[level_files.num_files - 1].largest_key);
} else {
user_end = end->user_key();
end = &level_files.files[level_files.num_files - 1].file_metadata->largest;
}
GetOverlappingInputsRangeBinarySearch(level, user_begin, user_end, inputs,
GetOverlappingInputsRangeBinarySearch(level, begin, end, inputs,
hint_index, file_index,
true /* within_interval */);
}
namespace {
const uint64_t kRangeTombstoneSentinel =
PackSequenceAndType(kMaxSequenceNumber, kTypeRangeDeletion);
// Utility for comparing sstable boundary keys. Returns -1 if either a or b is
// null which provides the property that a==null indicates a key that is less
// than any key and b==null indicates a key that is greater than any key. Note
// that the comparison is performed primarily on the user-key portion of the
// key. If the user-keys compare equal, an additional test is made to sort
// range tombstone sentinel keys before other keys with the same user-key. The
// result is that 2 user-keys will compare equal if they differ purely on
// their sequence number and value, but the range tombstone sentinel for that
// user-key will compare not equal. This is necessary because the range
// tombstone sentinel key is set as the largest key for an sstable even though
// that key never appears in the database. We don't want adjacent sstables to
// be considered overlapping if they are separated by the range tombstone
// sentinel.
int sstableKeyCompare(const Comparator* user_cmp,
const InternalKey& a, const InternalKey& b) {
auto c = user_cmp->Compare(a.user_key(), b.user_key());
if (c != 0) {
return c;
}
auto a_footer = ExtractInternalKeyFooter(a.Encode());
auto b_footer = ExtractInternalKeyFooter(b.Encode());
if (a_footer == kRangeTombstoneSentinel) {
if (b_footer != kRangeTombstoneSentinel) {
return -1;
}
} else if (b_footer == kRangeTombstoneSentinel) {
return 1;
}
return 0;
}
int sstableKeyCompare(const Comparator* user_cmp,
const InternalKey* a, const InternalKey& b) {
if (a == nullptr) {
return -1;
}
return sstableKeyCompare(user_cmp, *a, b);
}
int sstableKeyCompare(const Comparator* user_cmp,
const InternalKey& a, const InternalKey* b) {
if (b == nullptr) {
return -1;
}
return sstableKeyCompare(user_cmp, a, *b);
}
} // namespace
// Store in "*inputs" all files in "level" that overlap [begin,end]
// Employ binary search to find at least one file that overlaps the
// specified range. From that file, iterate backwards and
@ -2135,7 +2185,7 @@ void VersionStorageInfo::GetCleanInputsWithinInterval(
// within range [begin, end]. "clean" means there is a boudnary
// between the files in "*inputs" and the surrounding files
void VersionStorageInfo::GetOverlappingInputsRangeBinarySearch(
int level, const Slice& user_begin, const Slice& user_end,
int level, const InternalKey* begin, const InternalKey* end,
std::vector<FileMetaData*>* inputs, int hint_index, int* file_index,
bool within_interval) const {
assert(level > 0);
@ -2143,7 +2193,7 @@ void VersionStorageInfo::GetOverlappingInputsRangeBinarySearch(
int mid = 0;
int max = static_cast<int>(files_[level].size()) - 1;
bool foundOverlap = false;
const Comparator* user_cmp = user_comparator_;
auto user_cmp = user_comparator_;
// if the caller already knows the index of a file that has overlap,
// then we can skip the binary search.
@ -2155,15 +2205,15 @@ void VersionStorageInfo::GetOverlappingInputsRangeBinarySearch(
while (!foundOverlap && min <= max) {
mid = (min + max)/2;
FdWithKeyRange* f = &(level_files_brief_[level].files[mid]);
const Slice file_start = ExtractUserKey(f->smallest_key);
const Slice file_limit = ExtractUserKey(f->largest_key);
if ((!within_interval && user_cmp->Compare(file_limit, user_begin) < 0) ||
(within_interval && user_cmp->Compare(file_start, user_begin) < 0)) {
auto& smallest = f->file_metadata->smallest;
auto& largest = f->file_metadata->largest;
if ((!within_interval && sstableKeyCompare(user_cmp, begin, largest) > 0) ||
(within_interval && sstableKeyCompare(user_cmp, begin, smallest) > 0)) {
min = mid + 1;
} else if ((!within_interval &&
user_cmp->Compare(user_end, file_start) < 0) ||
sstableKeyCompare(user_cmp, smallest, end) > 0) ||
(within_interval &&
user_cmp->Compare(user_end, file_limit) < 0)) {
sstableKeyCompare(user_cmp, largest, end) > 0)) {
max = mid - 1;
} else {
foundOverlap = true;
@ -2182,10 +2232,10 @@ void VersionStorageInfo::GetOverlappingInputsRangeBinarySearch(
int start_index, end_index;
if (within_interval) {
ExtendFileRangeWithinInterval(level, user_begin, user_end, mid, &start_index,
&end_index);
ExtendFileRangeWithinInterval(level, begin, end, mid,
&start_index, &end_index);
} else {
ExtendFileRangeOverlappingInterval(level, user_begin, user_end, mid,
ExtendFileRangeOverlappingInterval(level, begin, end, mid,
&start_index, &end_index);
assert(end_index >= start_index);
}
@ -2202,21 +2252,28 @@ void VersionStorageInfo::GetOverlappingInputsRangeBinarySearch(
// and forward to find all overlapping files.
// Use FileLevel in searching, make it faster
void VersionStorageInfo::ExtendFileRangeOverlappingInterval(
int level, const Slice& user_begin, const Slice& user_end,
int level, const InternalKey* begin, const InternalKey* end,
unsigned int mid_index, int* start_index, int* end_index) const {
const Comparator* user_cmp = user_comparator_;
auto user_cmp = user_comparator_;
const FdWithKeyRange* files = level_files_brief_[level].files;
#ifndef NDEBUG
{
// assert that the file at mid_index overlaps with the range
assert(mid_index < level_files_brief_[level].num_files);
const FdWithKeyRange* f = &files[mid_index];
const Slice fstart = ExtractUserKey(f->smallest_key);
const Slice flimit = ExtractUserKey(f->largest_key);
if (user_cmp->Compare(fstart, user_begin) >= 0) {
assert(user_cmp->Compare(fstart, user_end) <= 0);
auto& smallest = f->file_metadata->smallest;
auto& largest = f->file_metadata->largest;
if (sstableKeyCompare(user_cmp, begin, smallest) <= 0) {
assert(sstableKeyCompare(user_cmp, smallest, end) <= 0);
} else {
assert(user_cmp->Compare(flimit, user_begin) >= 0);
// fprintf(stderr, "ExtendFileRangeOverlappingInterval\n%s - %s\n%s - %s\n%d %d\n",
// begin ? begin->DebugString().c_str() : "(null)",
// end ? end->DebugString().c_str() : "(null)",
// smallest->DebugString().c_str(),
// largest->DebugString().c_str(),
// sstableKeyCompare(user_cmp, smallest, begin),
// sstableKeyCompare(user_cmp, largest, begin));
assert(sstableKeyCompare(user_cmp, begin, largest) <= 0);
}
}
#endif
@ -2228,8 +2285,8 @@ void VersionStorageInfo::ExtendFileRangeOverlappingInterval(
// check backwards from 'mid' to lower indices
for (int i = mid_index; i >= 0 ; i--) {
const FdWithKeyRange* f = &files[i];
const Slice file_limit = ExtractUserKey(f->largest_key);
if (user_cmp->Compare(file_limit, user_begin) >= 0) {
auto& largest = f->file_metadata->largest;
if (sstableKeyCompare(user_cmp, begin, largest) <= 0) {
*start_index = i;
assert((count++, true));
} else {
@ -2240,8 +2297,8 @@ void VersionStorageInfo::ExtendFileRangeOverlappingInterval(
for (unsigned int i = mid_index+1;
i < level_files_brief_[level].num_files; i++) {
const FdWithKeyRange* f = &files[i];
const Slice file_start = ExtractUserKey(f->smallest_key);
if (user_cmp->Compare(file_start, user_end) <= 0) {
auto& smallest = f->file_metadata->smallest;
if (sstableKeyCompare(user_cmp, smallest, end) <= 0) {
assert((count++, true));
*end_index = i;
} else {
@ -2259,39 +2316,36 @@ void VersionStorageInfo::ExtendFileRangeOverlappingInterval(
// the clean range required.
// Use FileLevel in searching, make it faster
void VersionStorageInfo::ExtendFileRangeWithinInterval(
int level, const Slice& user_begin, const Slice& user_end,
int level, const InternalKey* begin, const InternalKey* end,
unsigned int mid_index, int* start_index, int* end_index) const {
assert(level != 0);
const Comparator* user_cmp = user_comparator_;
auto* user_cmp = user_comparator_;
const FdWithKeyRange* files = level_files_brief_[level].files;
#ifndef NDEBUG
{
// assert that the file at mid_index is within the range
assert(mid_index < level_files_brief_[level].num_files);
const FdWithKeyRange* f = &files[mid_index];
const Slice fstart = ExtractUserKey(f->smallest_key);
const Slice flimit = ExtractUserKey(f->largest_key);
assert(user_cmp->Compare(fstart, user_begin) >= 0 &&
user_cmp->Compare(flimit, user_end) <= 0);
auto& smallest = f->file_metadata->smallest;
auto& largest = f->file_metadata->largest;
assert(sstableKeyCompare(user_cmp, begin, smallest) <= 0 &&
sstableKeyCompare(user_cmp, largest, end) <= 0);
}
#endif
ExtendFileRangeOverlappingInterval(level, user_begin, user_end, mid_index,
ExtendFileRangeOverlappingInterval(level, begin, end, mid_index,
start_index, end_index);
int left = *start_index;
int right = *end_index;
// shrink from left to right
while (left <= right) {
const Slice& first_key_in_range = ExtractUserKey(files[left].smallest_key);
if (user_cmp->Compare(first_key_in_range, user_begin) < 0) {
auto& smallest = files[left].file_metadata->smallest;
if (sstableKeyCompare(user_cmp, begin, smallest) > 0) {
left++;
continue;
}
if (left > 0) { // If not first file
const Slice& last_key_before =
ExtractUserKey(files[left - 1].largest_key);
if (user_cmp->Equal(first_key_in_range, last_key_before)) {
// The first user key in range overlaps with the previous file's last
// key
auto& largest = files[left - 1].file_metadata->largest;
if (sstableKeyCompare(user_cmp, smallest, largest) == 0) {
left++;
continue;
}
@ -2300,16 +2354,15 @@ void VersionStorageInfo::ExtendFileRangeWithinInterval(
}
// shrink from right to left
while (left <= right) {
const Slice last_key_in_range = ExtractUserKey(files[right].largest_key);
if (user_cmp->Compare(last_key_in_range, user_end) > 0) {
auto& largest = files[right].file_metadata->largest;
if (sstableKeyCompare(user_cmp, largest, end) > 0) {
right--;
continue;
}
if (right < static_cast<int>(level_files_brief_[level].num_files) -
1) { // If not the last file
const Slice first_key_after =
ExtractUserKey(files[right + 1].smallest_key);
if (user_cmp->Equal(last_key_in_range, first_key_after)) {
auto& smallest = files[right + 1].file_metadata->smallest;
if (sstableKeyCompare(user_cmp, smallest, largest) == 0) {
// The last user key in range overlaps with the next file's first key
right--;
continue;
@ -4030,8 +4083,8 @@ uint64_t VersionSet::ApproximateSize(Version* v, const FdWithKeyRange& f,
// approximate offset of "key" within the table.
TableReader* table_reader_ptr;
InternalIterator* iter = v->cfd_->table_cache()->NewIterator(
ReadOptions(), v->env_options_, v->cfd_->internal_comparator(), f.fd,
nullptr /* range_del_agg */,
ReadOptions(), v->env_options_, v->cfd_->internal_comparator(),
*f.file_metadata, nullptr /* range_del_agg */,
v->GetMutableCFOptions().prefix_extractor.get(), &table_reader_ptr);
if (table_reader_ptr != nullptr) {
result = table_reader_ptr->ApproximateOffsetOf(key);
@ -4111,7 +4164,7 @@ InternalIterator* VersionSet::MakeInputIterator(
for (size_t i = 0; i < flevel->num_files; i++) {
list[num++] = cfd->table_cache()->NewIterator(
read_options, env_options_compactions, cfd->internal_comparator(),
flevel->files[i].fd, range_del_agg,
*flevel->files[i].file_metadata, range_del_agg,
c->mutable_cf_options()->prefix_extractor.get(),
nullptr /* table_reader_ptr */,
nullptr /* no per level latency histogram */,

24
db/version_set.h
View File

@ -201,8 +201,8 @@ class VersionStorageInfo {
void GetOverlappingInputsRangeBinarySearch(
int level, // level > 0
const Slice& begin, // nullptr means before all keys
const Slice& end, // nullptr means after all keys
const InternalKey* begin, // nullptr means before all keys
const InternalKey* end, // nullptr means after all keys
std::vector<FileMetaData*>* inputs,
int hint_index, // index of overlap file
int* file_index, // return index of overlap file
@ -211,20 +211,20 @@ class VersionStorageInfo {
void ExtendFileRangeOverlappingInterval(
int level,
const Slice& begin, // nullptr means before all keys
const Slice& end, // nullptr means after all keys
unsigned int index, // start extending from this index
int* startIndex, // return the startIndex of input range
int* endIndex) // return the endIndex of input range
const InternalKey* begin, // nullptr means before all keys
const InternalKey* end, // nullptr means after all keys
unsigned int index, // start extending from this index
int* startIndex, // return the startIndex of input range
int* endIndex) // return the endIndex of input range
const;
void ExtendFileRangeWithinInterval(
int level,
const Slice& begin, // nullptr means before all keys
const Slice& end, // nullptr means after all keys
unsigned int index, // start extending from this index
int* startIndex, // return the startIndex of input range
int* endIndex) // return the endIndex of input range
const InternalKey* begin, // nullptr means before all keys
const InternalKey* end, // nullptr means after all keys
unsigned int index, // start extending from this index
int* startIndex, // return the startIndex of input range
int* endIndex) // return the endIndex of input range
const;
// Returns true iff some file in the specified level overlaps

64
db/version_set_test.cc
View File

@ -11,6 +11,7 @@
#include "db/log_writer.h"
#include "table/mock_table.h"
#include "util/logging.h"
#include "util/string_util.h"
#include "util/testharness.h"
#include "util/testutil.h"
@ -139,6 +140,35 @@ class VersionStorageInfoTest : public testing::Test {
f->num_deletions = 0;
vstorage_.AddFile(level, f);
}
void Add(int level, uint32_t file_number, const InternalKey& smallest,
const InternalKey& largest, uint64_t file_size = 0) {
assert(level < vstorage_.num_levels());
FileMetaData* f = new FileMetaData;
f->fd = FileDescriptor(file_number, 0, file_size);
f->smallest = smallest;
f->largest = largest;
f->compensated_file_size = file_size;
f->refs = 0;
f->num_entries = 0;
f->num_deletions = 0;
vstorage_.AddFile(level, f);
}
std::string GetOverlappingFiles(int level, const InternalKey& begin,
const InternalKey& end) {
std::vector<FileMetaData*> inputs;
vstorage_.GetOverlappingInputs(level, &begin, &end, &inputs);
std::string result;
for (size_t i = 0; i < inputs.size(); ++i) {
if (i > 0) {
result += ",";
}
AppendNumberTo(&result, inputs[i]->fd.GetNumber());
}
return result;
}
};
TEST_F(VersionStorageInfoTest, MaxBytesForLevelStatic) {
@ -261,6 +291,40 @@ TEST_F(VersionStorageInfoTest, EstimateLiveDataSize2) {
ASSERT_EQ(4U, vstorage_.EstimateLiveDataSize());
}
TEST_F(VersionStorageInfoTest, GetOverlappingInputs) {
// Two files that overlap at the range deletion tombstone sentinel.
Add(1, 1U, {"a", 0, kTypeValue}, {"b", kMaxSequenceNumber, kTypeRangeDeletion}, 1);
Add(1, 2U, {"b", 0, kTypeValue}, {"c", 0, kTypeValue}, 1);
// Two files that overlap at the same user key.
Add(1, 3U, {"d", 0, kTypeValue}, {"e", kMaxSequenceNumber, kTypeValue}, 1);
Add(1, 4U, {"e", 0, kTypeValue}, {"f", 0, kTypeValue}, 1);
// Two files that do not overlap.
Add(1, 5U, {"g", 0, kTypeValue}, {"h", 0, kTypeValue}, 1);
Add(1, 6U, {"i", 0, kTypeValue}, {"j", 0, kTypeValue}, 1);
vstorage_.UpdateNumNonEmptyLevels();
vstorage_.GenerateLevelFilesBrief();
ASSERT_EQ("1,2", GetOverlappingFiles(
1, {"a", 0, kTypeValue}, {"b", 0, kTypeValue}));
ASSERT_EQ("1", GetOverlappingFiles(
1, {"a", 0, kTypeValue}, {"b", kMaxSequenceNumber, kTypeRangeDeletion}));
ASSERT_EQ("2", GetOverlappingFiles(
1, {"b", kMaxSequenceNumber, kTypeValue}, {"c", 0, kTypeValue}));
ASSERT_EQ("3,4", GetOverlappingFiles(
1, {"d", 0, kTypeValue}, {"e", 0, kTypeValue}));
ASSERT_EQ("3", GetOverlappingFiles(
1, {"d", 0, kTypeValue}, {"e", kMaxSequenceNumber, kTypeRangeDeletion}));
ASSERT_EQ("3,4", GetOverlappingFiles(
1, {"e", kMaxSequenceNumber, kTypeValue}, {"f", 0, kTypeValue}));
ASSERT_EQ("3,4", GetOverlappingFiles(
1, {"e", 0, kTypeValue}, {"f", 0, kTypeValue}));
ASSERT_EQ("5", GetOverlappingFiles(
1, {"g", 0, kTypeValue}, {"h", 0, kTypeValue}));
ASSERT_EQ("6", GetOverlappingFiles(
1, {"i", 0, kTypeValue}, {"j", 0, kTypeValue}));
}
class FindLevelFileTest : public testing::Test {
public:
LevelFilesBrief file_level_;