1b114eed4d
Summary: This diff improves the memory utilization for tailing iterators RocksDB, by freeing file iterators which are over the upper bound. It is an updating on Siying's original diff for improving the memory usage for tailing iterators. The changes for the seek and next path are now complete and a test has been added to exercise these paths while deleting file iterators which are above the upper bound. Test Plan: db_tailing_iter_test.TailingIteratorTrimSeekToNext Reviewers: march, tnovak, sdong Reviewed By: sdong Subscribers: dhruba Differential Revision: https://reviews.facebook.net/D43833
564 lines
16 KiB
C++
564 lines
16 KiB
C++
// Copyright (c) 2013, Facebook, Inc. All rights reserved.
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// This source code is licensed under the BSD-style license found in the
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// LICENSE file in the root directory of this source tree. An additional grant
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// of patent rights can be found in the PATENTS file in the same directory.
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//
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// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
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// Use of this source code is governed by a BSD-style license that can be
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// found in the LICENSE file. See the AUTHORS file for names of contributors.
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// Introduction of SyncPoint effectively disabled building and running this test
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// in Release build.
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// which is a pity, it is a good test
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#if !(defined NDEBUG) || !defined(OS_WIN)
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#include "port/stack_trace.h"
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#include "util/db_test_util.h"
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namespace rocksdb {
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class DBTestTailingIterator : public DBTestBase {
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public:
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DBTestTailingIterator() : DBTestBase("/db_tailing_iterator_test") {}
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};
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TEST_F(DBTestTailingIterator, TailingIteratorSingle) {
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ReadOptions read_options;
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read_options.tailing = true;
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std::unique_ptr<Iterator> iter(db_->NewIterator(read_options));
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iter->SeekToFirst();
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ASSERT_TRUE(!iter->Valid());
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// add a record and check that iter can see it
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ASSERT_OK(db_->Put(WriteOptions(), "mirko", "fodor"));
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iter->SeekToFirst();
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ASSERT_TRUE(iter->Valid());
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ASSERT_EQ(iter->key().ToString(), "mirko");
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iter->Next();
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ASSERT_TRUE(!iter->Valid());
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}
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TEST_F(DBTestTailingIterator, TailingIteratorKeepAdding) {
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CreateAndReopenWithCF({"pikachu"}, CurrentOptions());
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ReadOptions read_options;
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read_options.tailing = true;
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std::unique_ptr<Iterator> iter(db_->NewIterator(read_options, handles_[1]));
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std::string value(1024, 'a');
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const int num_records = 10000;
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for (int i = 0; i < num_records; ++i) {
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char buf[32];
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snprintf(buf, sizeof(buf), "%016d", i);
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Slice key(buf, 16);
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ASSERT_OK(Put(1, key, value));
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iter->Seek(key);
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ASSERT_TRUE(iter->Valid());
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ASSERT_EQ(iter->key().compare(key), 0);
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}
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}
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TEST_F(DBTestTailingIterator, TailingIteratorSeekToNext) {
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CreateAndReopenWithCF({"pikachu"}, CurrentOptions());
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ReadOptions read_options;
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read_options.tailing = true;
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std::unique_ptr<Iterator> iter(db_->NewIterator(read_options, handles_[1]));
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std::unique_ptr<Iterator> itern(db_->NewIterator(read_options, handles_[1]));
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std::string value(1024, 'a');
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const int num_records = 1000;
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for (int i = 1; i < num_records; ++i) {
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char buf1[32];
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char buf2[32];
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snprintf(buf1, sizeof(buf1), "00a0%016d", i * 5);
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Slice key(buf1, 20);
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ASSERT_OK(Put(1, key, value));
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if (i % 100 == 99) {
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ASSERT_OK(Flush(1));
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}
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snprintf(buf2, sizeof(buf2), "00a0%016d", i * 5 - 2);
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Slice target(buf2, 20);
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iter->Seek(target);
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ASSERT_TRUE(iter->Valid());
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ASSERT_EQ(iter->key().compare(key), 0);
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if (i == 1) {
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itern->SeekToFirst();
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} else {
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itern->Next();
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}
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ASSERT_TRUE(itern->Valid());
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ASSERT_EQ(itern->key().compare(key), 0);
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}
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for (int i = 2 * num_records; i > 0; --i) {
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char buf1[32];
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char buf2[32];
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snprintf(buf1, sizeof(buf1), "00a0%016d", i * 5);
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Slice key(buf1, 20);
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ASSERT_OK(Put(1, key, value));
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if (i % 100 == 99) {
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ASSERT_OK(Flush(1));
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}
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snprintf(buf2, sizeof(buf2), "00a0%016d", i * 5 - 2);
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Slice target(buf2, 20);
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iter->Seek(target);
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ASSERT_TRUE(iter->Valid());
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ASSERT_EQ(iter->key().compare(key), 0);
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}
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}
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TEST_F(DBTestTailingIterator, TailingIteratorTrimSeekToNext) {
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CreateAndReopenWithCF({"pikachu"}, CurrentOptions());
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ReadOptions read_options;
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read_options.tailing = true;
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char bufe[32];
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snprintf(bufe, sizeof(bufe), "00b0%016d", 0);
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Slice keyu(bufe, 20);
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read_options.iterate_upper_bound = &keyu;
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std::unique_ptr<Iterator> iter(db_->NewIterator(read_options, handles_[1]));
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std::unique_ptr<Iterator> itern(db_->NewIterator(read_options, handles_[1]));
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std::unique_ptr<Iterator> iterh(db_->NewIterator(read_options, handles_[1]));
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std::string value(1024, 'a');
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const int num_records = 1000;
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for (int i = 1; i < num_records; ++i) {
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char buf1[32];
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char buf2[32];
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char buf3[32];
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char buf4[32];
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snprintf(buf1, sizeof(buf1), "00a0%016d", i * 5);
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snprintf(buf3, sizeof(buf1), "00b0%016d", i * 5);
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Slice key(buf1, 20);
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ASSERT_OK(Put(1, key, value));
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Slice keyn(buf3, 20);
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ASSERT_OK(Put(1, keyn, value));
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if (i % 100 == 99) {
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ASSERT_OK(Flush(1));
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dbfull()->TEST_WaitForCompact();
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snprintf(buf4, sizeof(buf1), "00a0%016d", i * 5 / 2);
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Slice target(buf4, 20);
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iterh->Seek(target);
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ASSERT_TRUE(iter->Valid());
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for (int j = (i + 1) * 5 / 2; j < i * 5; j += 5) {
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iterh->Next();
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ASSERT_TRUE(iterh->Valid());
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}
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}
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snprintf(buf2, sizeof(buf2), "00a0%016d", i * 5 - 2);
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Slice target(buf2, 20);
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iter->Seek(target);
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ASSERT_TRUE(iter->Valid());
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ASSERT_EQ(iter->key().compare(key), 0);
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if (i == 1) {
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itern->SeekToFirst();
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} else {
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itern->Next();
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}
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ASSERT_TRUE(itern->Valid());
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ASSERT_EQ(itern->key().compare(key), 0);
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}
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for (int i = 2 * num_records; i > 0; --i) {
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char buf1[32];
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char buf2[32];
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snprintf(buf1, sizeof(buf1), "00a0%016d", i * 5);
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Slice key(buf1, 20);
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ASSERT_OK(Put(1, key, value));
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if (i % 100 == 99) {
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ASSERT_OK(Flush(1));
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}
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snprintf(buf2, sizeof(buf2), "00a0%016d", i * 5 - 2);
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Slice target(buf2, 20);
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iter->Seek(target);
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ASSERT_TRUE(iter->Valid());
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ASSERT_EQ(iter->key().compare(key), 0);
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}
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}
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TEST_F(DBTestTailingIterator, TailingIteratorDeletes) {
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CreateAndReopenWithCF({"pikachu"}, CurrentOptions());
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ReadOptions read_options;
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read_options.tailing = true;
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std::unique_ptr<Iterator> iter(db_->NewIterator(read_options, handles_[1]));
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// write a single record, read it using the iterator, then delete it
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ASSERT_OK(Put(1, "0test", "test"));
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iter->SeekToFirst();
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ASSERT_TRUE(iter->Valid());
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ASSERT_EQ(iter->key().ToString(), "0test");
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ASSERT_OK(Delete(1, "0test"));
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// write many more records
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const int num_records = 10000;
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std::string value(1024, 'A');
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for (int i = 0; i < num_records; ++i) {
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char buf[32];
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snprintf(buf, sizeof(buf), "1%015d", i);
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Slice key(buf, 16);
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ASSERT_OK(Put(1, key, value));
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}
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// force a flush to make sure that no records are read from memtable
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ASSERT_OK(Flush(1));
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// skip "0test"
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iter->Next();
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// make sure we can read all new records using the existing iterator
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int count = 0;
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for (; iter->Valid(); iter->Next(), ++count) ;
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ASSERT_EQ(count, num_records);
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}
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TEST_F(DBTestTailingIterator, TailingIteratorPrefixSeek) {
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XFUNC_TEST("", "dbtest_prefix", prefix_skip1, XFuncPoint::SetSkip,
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kSkipNoPrefix);
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ReadOptions read_options;
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read_options.tailing = true;
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Options options = CurrentOptions();
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options.env = env_;
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options.create_if_missing = true;
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options.disable_auto_compactions = true;
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options.prefix_extractor.reset(NewFixedPrefixTransform(2));
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options.memtable_factory.reset(NewHashSkipListRepFactory(16));
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DestroyAndReopen(options);
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CreateAndReopenWithCF({"pikachu"}, options);
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std::unique_ptr<Iterator> iter(db_->NewIterator(read_options, handles_[1]));
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ASSERT_OK(Put(1, "0101", "test"));
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ASSERT_OK(Flush(1));
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ASSERT_OK(Put(1, "0202", "test"));
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// Seek(0102) shouldn't find any records since 0202 has a different prefix
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iter->Seek("0102");
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ASSERT_TRUE(!iter->Valid());
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iter->Seek("0202");
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ASSERT_TRUE(iter->Valid());
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ASSERT_EQ(iter->key().ToString(), "0202");
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iter->Next();
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ASSERT_TRUE(!iter->Valid());
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XFUNC_TEST("", "dbtest_prefix", prefix_skip1, XFuncPoint::SetSkip, 0);
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}
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TEST_F(DBTestTailingIterator, TailingIteratorIncomplete) {
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CreateAndReopenWithCF({"pikachu"}, CurrentOptions());
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ReadOptions read_options;
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read_options.tailing = true;
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read_options.read_tier = kBlockCacheTier;
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std::string key("key");
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std::string value("value");
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ASSERT_OK(db_->Put(WriteOptions(), key, value));
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std::unique_ptr<Iterator> iter(db_->NewIterator(read_options));
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iter->SeekToFirst();
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// we either see the entry or it's not in cache
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ASSERT_TRUE(iter->Valid() || iter->status().IsIncomplete());
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ASSERT_OK(db_->CompactRange(CompactRangeOptions(), nullptr, nullptr));
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iter->SeekToFirst();
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// should still be true after compaction
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ASSERT_TRUE(iter->Valid() || iter->status().IsIncomplete());
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}
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TEST_F(DBTestTailingIterator, TailingIteratorSeekToSame) {
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Options options = CurrentOptions();
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options.compaction_style = kCompactionStyleUniversal;
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options.write_buffer_size = 1000;
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CreateAndReopenWithCF({"pikachu"}, options);
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ReadOptions read_options;
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read_options.tailing = true;
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const int NROWS = 10000;
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// Write rows with keys 00000, 00002, 00004 etc.
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for (int i = 0; i < NROWS; ++i) {
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char buf[100];
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snprintf(buf, sizeof(buf), "%05d", 2*i);
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std::string key(buf);
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std::string value("value");
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ASSERT_OK(db_->Put(WriteOptions(), key, value));
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}
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std::unique_ptr<Iterator> iter(db_->NewIterator(read_options));
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// Seek to 00001. We expect to find 00002.
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std::string start_key = "00001";
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iter->Seek(start_key);
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ASSERT_TRUE(iter->Valid());
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std::string found = iter->key().ToString();
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ASSERT_EQ("00002", found);
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// Now seek to the same key. The iterator should remain in the same
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// position.
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iter->Seek(found);
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ASSERT_TRUE(iter->Valid());
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ASSERT_EQ(found, iter->key().ToString());
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}
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TEST_F(DBTestTailingIterator, ManagedTailingIteratorSingle) {
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ReadOptions read_options;
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read_options.tailing = true;
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read_options.managed = true;
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std::unique_ptr<Iterator> iter(db_->NewIterator(read_options));
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iter->SeekToFirst();
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ASSERT_TRUE(!iter->Valid());
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// add a record and check that iter can see it
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ASSERT_OK(db_->Put(WriteOptions(), "mirko", "fodor"));
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iter->SeekToFirst();
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ASSERT_TRUE(iter->Valid());
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ASSERT_EQ(iter->key().ToString(), "mirko");
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iter->Next();
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ASSERT_TRUE(!iter->Valid());
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}
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TEST_F(DBTestTailingIterator, ManagedTailingIteratorKeepAdding) {
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CreateAndReopenWithCF({"pikachu"}, CurrentOptions());
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ReadOptions read_options;
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read_options.tailing = true;
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read_options.managed = true;
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std::unique_ptr<Iterator> iter(db_->NewIterator(read_options, handles_[1]));
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std::string value(1024, 'a');
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const int num_records = 10000;
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for (int i = 0; i < num_records; ++i) {
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char buf[32];
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snprintf(buf, sizeof(buf), "%016d", i);
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Slice key(buf, 16);
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ASSERT_OK(Put(1, key, value));
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iter->Seek(key);
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ASSERT_TRUE(iter->Valid());
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ASSERT_EQ(iter->key().compare(key), 0);
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}
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}
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TEST_F(DBTestTailingIterator, ManagedTailingIteratorSeekToNext) {
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CreateAndReopenWithCF({"pikachu"}, CurrentOptions());
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ReadOptions read_options;
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read_options.tailing = true;
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read_options.managed = true;
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std::unique_ptr<Iterator> iter(db_->NewIterator(read_options, handles_[1]));
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std::string value(1024, 'a');
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const int num_records = 1000;
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for (int i = 1; i < num_records; ++i) {
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char buf1[32];
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char buf2[32];
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snprintf(buf1, sizeof(buf1), "00a0%016d", i * 5);
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Slice key(buf1, 20);
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ASSERT_OK(Put(1, key, value));
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if (i % 100 == 99) {
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ASSERT_OK(Flush(1));
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}
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snprintf(buf2, sizeof(buf2), "00a0%016d", i * 5 - 2);
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Slice target(buf2, 20);
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iter->Seek(target);
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ASSERT_TRUE(iter->Valid());
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ASSERT_EQ(iter->key().compare(key), 0);
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}
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for (int i = 2 * num_records; i > 0; --i) {
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char buf1[32];
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char buf2[32];
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snprintf(buf1, sizeof(buf1), "00a0%016d", i * 5);
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Slice key(buf1, 20);
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ASSERT_OK(Put(1, key, value));
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if (i % 100 == 99) {
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ASSERT_OK(Flush(1));
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}
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snprintf(buf2, sizeof(buf2), "00a0%016d", i * 5 - 2);
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Slice target(buf2, 20);
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iter->Seek(target);
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ASSERT_TRUE(iter->Valid());
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ASSERT_EQ(iter->key().compare(key), 0);
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}
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}
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TEST_F(DBTestTailingIterator, ManagedTailingIteratorDeletes) {
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CreateAndReopenWithCF({"pikachu"}, CurrentOptions());
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ReadOptions read_options;
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read_options.tailing = true;
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read_options.managed = true;
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std::unique_ptr<Iterator> iter(db_->NewIterator(read_options, handles_[1]));
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// write a single record, read it using the iterator, then delete it
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ASSERT_OK(Put(1, "0test", "test"));
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iter->SeekToFirst();
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ASSERT_TRUE(iter->Valid());
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ASSERT_EQ(iter->key().ToString(), "0test");
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ASSERT_OK(Delete(1, "0test"));
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// write many more records
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const int num_records = 10000;
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std::string value(1024, 'A');
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for (int i = 0; i < num_records; ++i) {
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char buf[32];
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snprintf(buf, sizeof(buf), "1%015d", i);
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Slice key(buf, 16);
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ASSERT_OK(Put(1, key, value));
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}
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// force a flush to make sure that no records are read from memtable
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ASSERT_OK(Flush(1));
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// skip "0test"
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iter->Next();
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// make sure we can read all new records using the existing iterator
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int count = 0;
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for (; iter->Valid(); iter->Next(), ++count) {
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}
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ASSERT_EQ(count, num_records);
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}
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TEST_F(DBTestTailingIterator, ManagedTailingIteratorPrefixSeek) {
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XFUNC_TEST("", "dbtest_prefix", prefix_skip1, XFuncPoint::SetSkip,
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kSkipNoPrefix);
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ReadOptions read_options;
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read_options.tailing = true;
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read_options.managed = true;
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Options options = CurrentOptions();
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options.env = env_;
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options.create_if_missing = true;
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options.disable_auto_compactions = true;
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options.prefix_extractor.reset(NewFixedPrefixTransform(2));
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options.memtable_factory.reset(NewHashSkipListRepFactory(16));
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DestroyAndReopen(options);
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CreateAndReopenWithCF({"pikachu"}, options);
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std::unique_ptr<Iterator> iter(db_->NewIterator(read_options, handles_[1]));
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ASSERT_OK(Put(1, "0101", "test"));
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ASSERT_OK(Flush(1));
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ASSERT_OK(Put(1, "0202", "test"));
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// Seek(0102) shouldn't find any records since 0202 has a different prefix
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iter->Seek("0102");
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ASSERT_TRUE(!iter->Valid());
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iter->Seek("0202");
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ASSERT_TRUE(iter->Valid());
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ASSERT_EQ(iter->key().ToString(), "0202");
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iter->Next();
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ASSERT_TRUE(!iter->Valid());
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XFUNC_TEST("", "dbtest_prefix", prefix_skip1, XFuncPoint::SetSkip, 0);
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}
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TEST_F(DBTestTailingIterator, ManagedTailingIteratorIncomplete) {
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CreateAndReopenWithCF({"pikachu"}, CurrentOptions());
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ReadOptions read_options;
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read_options.tailing = true;
|
|
read_options.managed = true;
|
|
read_options.read_tier = kBlockCacheTier;
|
|
|
|
std::string key = "key";
|
|
std::string value = "value";
|
|
|
|
ASSERT_OK(db_->Put(WriteOptions(), key, value));
|
|
|
|
std::unique_ptr<Iterator> iter(db_->NewIterator(read_options));
|
|
iter->SeekToFirst();
|
|
// we either see the entry or it's not in cache
|
|
ASSERT_TRUE(iter->Valid() || iter->status().IsIncomplete());
|
|
|
|
ASSERT_OK(db_->CompactRange(CompactRangeOptions(), nullptr, nullptr));
|
|
iter->SeekToFirst();
|
|
// should still be true after compaction
|
|
ASSERT_TRUE(iter->Valid() || iter->status().IsIncomplete());
|
|
}
|
|
|
|
TEST_F(DBTestTailingIterator, ManagedTailingIteratorSeekToSame) {
|
|
Options options = CurrentOptions();
|
|
options.compaction_style = kCompactionStyleUniversal;
|
|
options.write_buffer_size = 1000;
|
|
CreateAndReopenWithCF({"pikachu"}, options);
|
|
|
|
ReadOptions read_options;
|
|
read_options.tailing = true;
|
|
read_options.managed = true;
|
|
|
|
const int NROWS = 10000;
|
|
// Write rows with keys 00000, 00002, 00004 etc.
|
|
for (int i = 0; i < NROWS; ++i) {
|
|
char buf[100];
|
|
snprintf(buf, sizeof(buf), "%05d", 2 * i);
|
|
std::string key(buf);
|
|
std::string value("value");
|
|
ASSERT_OK(db_->Put(WriteOptions(), key, value));
|
|
}
|
|
|
|
std::unique_ptr<Iterator> iter(db_->NewIterator(read_options));
|
|
// Seek to 00001. We expect to find 00002.
|
|
std::string start_key = "00001";
|
|
iter->Seek(start_key);
|
|
ASSERT_TRUE(iter->Valid());
|
|
|
|
std::string found = iter->key().ToString();
|
|
ASSERT_EQ("00002", found);
|
|
|
|
// Now seek to the same key. The iterator should remain in the same
|
|
// position.
|
|
iter->Seek(found);
|
|
ASSERT_TRUE(iter->Valid());
|
|
ASSERT_EQ(found, iter->key().ToString());
|
|
}
|
|
|
|
} // namespace rocksdb
|
|
|
|
#endif // !(defined NDEBUG) || !defined(OS_WIN)
|
|
|
|
int main(int argc, char** argv) {
|
|
#if !(defined NDEBUG) || !defined(OS_WIN)
|
|
rocksdb::port::InstallStackTraceHandler();
|
|
::testing::InitGoogleTest(&argc, argv);
|
|
return RUN_ALL_TESTS();
|
|
#else
|
|
return 0;
|
|
#endif
|
|
}
|