rocksdb/db/log_test.cc
Yanqin Jin 9358178edc Support for single-primary, multi-secondary instances (#4899)
Summary:
This PR allows RocksDB to run in single-primary, multi-secondary process mode.
The writer is a regular RocksDB (e.g. an `DBImpl`) instance playing the role of a primary.
Multiple `DBImplSecondary` processes (secondaries) share the same set of SST files, MANIFEST, WAL files with the primary. Secondaries tail the MANIFEST of the primary and apply updates to their own in-memory state of the file system, e.g. `VersionStorageInfo`.

This PR has several components:
1. (Originally in #4745). Add a `PathNotFound` subcode to `IOError` to denote the failure when a secondary tries to open a file which has been deleted by the primary.

2. (Similar to #4602). Add `FragmentBufferedReader` to handle partially-read, trailing record at the end of a log from where future read can continue.

3. (Originally in #4710 and #4820). Add implementation of the secondary, i.e. `DBImplSecondary`.
3.1 Tail the primary's MANIFEST during recovery.
3.2 Tail the primary's MANIFEST during normal processing by calling `ReadAndApply`.
3.3 Tailing WAL will be in a future PR.

4. Add an example in 'examples/multi_processes_example.cc' to demonstrate the usage of secondary RocksDB instance in a multi-process setting. Instructions to run the example can be found at the beginning of the source code.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4899

Differential Revision: D14510945

Pulled By: riversand963

fbshipit-source-id: 4ac1c5693e6012ad23f7b4b42d3c374fecbe8886
2019-03-26 16:45:31 -07:00

922 lines
28 KiB
C++

// 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 "db/log_reader.h"
#include "db/log_writer.h"
#include "rocksdb/env.h"
#include "util/coding.h"
#include "util/crc32c.h"
#include "util/file_reader_writer.h"
#include "util/random.h"
#include "util/testharness.h"
#include "util/testutil.h"
namespace rocksdb {
namespace log {
// Construct a string of the specified length made out of the supplied
// partial string.
static std::string BigString(const std::string& partial_string, size_t n) {
std::string result;
while (result.size() < n) {
result.append(partial_string);
}
result.resize(n);
return result;
}
// Construct a string from a number
static std::string NumberString(int n) {
char buf[50];
snprintf(buf, sizeof(buf), "%d.", n);
return std::string(buf);
}
// Return a skewed potentially long string
static std::string RandomSkewedString(int i, Random* rnd) {
return BigString(NumberString(i), rnd->Skewed(17));
}
// Param type is tuple<int, bool>
// get<0>(tuple): non-zero if recycling log, zero if regular log
// get<1>(tuple): true if allow retry after read EOF, false otherwise
class LogTest : public ::testing::TestWithParam<std::tuple<int, bool>> {
private:
class StringSource : public SequentialFile {
public:
Slice& contents_;
bool force_error_;
size_t force_error_position_;
bool force_eof_;
size_t force_eof_position_;
bool returned_partial_;
bool fail_after_read_partial_;
explicit StringSource(Slice& contents, bool fail_after_read_partial)
: contents_(contents),
force_error_(false),
force_error_position_(0),
force_eof_(false),
force_eof_position_(0),
returned_partial_(false),
fail_after_read_partial_(fail_after_read_partial) {}
Status Read(size_t n, Slice* result, char* scratch) override {
if (fail_after_read_partial_) {
EXPECT_TRUE(!returned_partial_) << "must not Read() after eof/error";
}
if (force_error_) {
if (force_error_position_ >= n) {
force_error_position_ -= n;
} else {
*result = Slice(contents_.data(), force_error_position_);
contents_.remove_prefix(force_error_position_);
force_error_ = false;
returned_partial_ = true;
return Status::Corruption("read error");
}
}
if (contents_.size() < n) {
n = contents_.size();
returned_partial_ = true;
}
if (force_eof_) {
if (force_eof_position_ >= n) {
force_eof_position_ -= n;
} else {
force_eof_ = false;
n = force_eof_position_;
returned_partial_ = true;
}
}
// By using scratch we ensure that caller has control over the
// lifetime of result.data()
memcpy(scratch, contents_.data(), n);
*result = Slice(scratch, n);
contents_.remove_prefix(n);
return Status::OK();
}
Status Skip(uint64_t n) override {
if (n > contents_.size()) {
contents_.clear();
return Status::NotFound("in-memory file skipepd past end");
}
contents_.remove_prefix(n);
return Status::OK();
}
};
class ReportCollector : public Reader::Reporter {
public:
size_t dropped_bytes_;
std::string message_;
ReportCollector() : dropped_bytes_(0) { }
void Corruption(size_t bytes, const Status& status) override {
dropped_bytes_ += bytes;
message_.append(status.ToString());
}
};
std::string& dest_contents() {
auto dest =
dynamic_cast<test::StringSink*>(writer_.file()->writable_file());
assert(dest);
return dest->contents_;
}
const std::string& dest_contents() const {
auto dest =
dynamic_cast<const test::StringSink*>(writer_.file()->writable_file());
assert(dest);
return dest->contents_;
}
void reset_source_contents() {
auto src = dynamic_cast<StringSource*>(reader_->file()->file());
assert(src);
src->contents_ = dest_contents();
}
Slice reader_contents_;
std::unique_ptr<WritableFileWriter> dest_holder_;
std::unique_ptr<SequentialFileReader> source_holder_;
ReportCollector report_;
Writer writer_;
std::unique_ptr<Reader> reader_;
protected:
bool allow_retry_read_;
public:
LogTest()
: reader_contents_(),
dest_holder_(test::GetWritableFileWriter(
new test::StringSink(&reader_contents_), "" /* don't care */)),
source_holder_(test::GetSequentialFileReader(
new StringSource(reader_contents_, !std::get<1>(GetParam())),
"" /* file name */)),
writer_(std::move(dest_holder_), 123, std::get<0>(GetParam())),
allow_retry_read_(std::get<1>(GetParam())) {
if (allow_retry_read_) {
reader_.reset(new FragmentBufferedReader(
nullptr, std::move(source_holder_), &report_, true /* checksum */,
123 /* log_number */));
} else {
reader_.reset(new Reader(nullptr, std::move(source_holder_), &report_,
true /* checksum */, 123 /* log_number */));
}
}
Slice* get_reader_contents() { return &reader_contents_; }
void Write(const std::string& msg) {
writer_.AddRecord(Slice(msg));
}
size_t WrittenBytes() const {
return dest_contents().size();
}
std::string Read(const WALRecoveryMode wal_recovery_mode =
WALRecoveryMode::kTolerateCorruptedTailRecords) {
std::string scratch;
Slice record;
bool ret = false;
ret = reader_->ReadRecord(&record, &scratch, wal_recovery_mode);
if (ret) {
return record.ToString();
} else {
return "EOF";
}
}
void IncrementByte(int offset, char delta) {
dest_contents()[offset] += delta;
}
void SetByte(int offset, char new_byte) {
dest_contents()[offset] = new_byte;
}
void ShrinkSize(int bytes) {
auto dest =
dynamic_cast<test::StringSink*>(writer_.file()->writable_file());
assert(dest);
dest->Drop(bytes);
}
void FixChecksum(int header_offset, int len, bool recyclable) {
// Compute crc of type/len/data
int header_size = recyclable ? kRecyclableHeaderSize : kHeaderSize;
uint32_t crc = crc32c::Value(&dest_contents()[header_offset + 6],
header_size - 6 + len);
crc = crc32c::Mask(crc);
EncodeFixed32(&dest_contents()[header_offset], crc);
}
void ForceError(size_t position = 0) {
auto src = dynamic_cast<StringSource*>(reader_->file()->file());
src->force_error_ = true;
src->force_error_position_ = position;
}
size_t DroppedBytes() const {
return report_.dropped_bytes_;
}
std::string ReportMessage() const {
return report_.message_;
}
void ForceEOF(size_t position = 0) {
auto src = dynamic_cast<StringSource*>(reader_->file()->file());
src->force_eof_ = true;
src->force_eof_position_ = position;
}
void UnmarkEOF() {
auto src = dynamic_cast<StringSource*>(reader_->file()->file());
src->returned_partial_ = false;
reader_->UnmarkEOF();
}
bool IsEOF() { return reader_->IsEOF(); }
// Returns OK iff recorded error message contains "msg"
std::string MatchError(const std::string& msg) const {
if (report_.message_.find(msg) == std::string::npos) {
return report_.message_;
} else {
return "OK";
}
}
};
TEST_P(LogTest, Empty) { ASSERT_EQ("EOF", Read()); }
TEST_P(LogTest, ReadWrite) {
Write("foo");
Write("bar");
Write("");
Write("xxxx");
ASSERT_EQ("foo", Read());
ASSERT_EQ("bar", Read());
ASSERT_EQ("", Read());
ASSERT_EQ("xxxx", Read());
ASSERT_EQ("EOF", Read());
ASSERT_EQ("EOF", Read()); // Make sure reads at eof work
}
TEST_P(LogTest, ManyBlocks) {
for (int i = 0; i < 100000; i++) {
Write(NumberString(i));
}
for (int i = 0; i < 100000; i++) {
ASSERT_EQ(NumberString(i), Read());
}
ASSERT_EQ("EOF", Read());
}
TEST_P(LogTest, Fragmentation) {
Write("small");
Write(BigString("medium", 50000));
Write(BigString("large", 100000));
ASSERT_EQ("small", Read());
ASSERT_EQ(BigString("medium", 50000), Read());
ASSERT_EQ(BigString("large", 100000), Read());
ASSERT_EQ("EOF", Read());
}
TEST_P(LogTest, MarginalTrailer) {
// Make a trailer that is exactly the same length as an empty record.
int header_size =
std::get<0>(GetParam()) ? kRecyclableHeaderSize : kHeaderSize;
const int n = kBlockSize - 2 * header_size;
Write(BigString("foo", n));
ASSERT_EQ((unsigned int)(kBlockSize - header_size), WrittenBytes());
Write("");
Write("bar");
ASSERT_EQ(BigString("foo", n), Read());
ASSERT_EQ("", Read());
ASSERT_EQ("bar", Read());
ASSERT_EQ("EOF", Read());
}
TEST_P(LogTest, MarginalTrailer2) {
// Make a trailer that is exactly the same length as an empty record.
int header_size =
std::get<0>(GetParam()) ? kRecyclableHeaderSize : kHeaderSize;
const int n = kBlockSize - 2 * header_size;
Write(BigString("foo", n));
ASSERT_EQ((unsigned int)(kBlockSize - header_size), WrittenBytes());
Write("bar");
ASSERT_EQ(BigString("foo", n), Read());
ASSERT_EQ("bar", Read());
ASSERT_EQ("EOF", Read());
ASSERT_EQ(0U, DroppedBytes());
ASSERT_EQ("", ReportMessage());
}
TEST_P(LogTest, ShortTrailer) {
int header_size =
std::get<0>(GetParam()) ? kRecyclableHeaderSize : kHeaderSize;
const int n = kBlockSize - 2 * header_size + 4;
Write(BigString("foo", n));
ASSERT_EQ((unsigned int)(kBlockSize - header_size + 4), WrittenBytes());
Write("");
Write("bar");
ASSERT_EQ(BigString("foo", n), Read());
ASSERT_EQ("", Read());
ASSERT_EQ("bar", Read());
ASSERT_EQ("EOF", Read());
}
TEST_P(LogTest, AlignedEof) {
int header_size =
std::get<0>(GetParam()) ? kRecyclableHeaderSize : kHeaderSize;
const int n = kBlockSize - 2 * header_size + 4;
Write(BigString("foo", n));
ASSERT_EQ((unsigned int)(kBlockSize - header_size + 4), WrittenBytes());
ASSERT_EQ(BigString("foo", n), Read());
ASSERT_EQ("EOF", Read());
}
TEST_P(LogTest, RandomRead) {
const int N = 500;
Random write_rnd(301);
for (int i = 0; i < N; i++) {
Write(RandomSkewedString(i, &write_rnd));
}
Random read_rnd(301);
for (int i = 0; i < N; i++) {
ASSERT_EQ(RandomSkewedString(i, &read_rnd), Read());
}
ASSERT_EQ("EOF", Read());
}
// Tests of all the error paths in log_reader.cc follow:
TEST_P(LogTest, ReadError) {
Write("foo");
ForceError();
ASSERT_EQ("EOF", Read());
ASSERT_EQ((unsigned int)kBlockSize, DroppedBytes());
ASSERT_EQ("OK", MatchError("read error"));
}
TEST_P(LogTest, BadRecordType) {
Write("foo");
// Type is stored in header[6]
IncrementByte(6, 100);
FixChecksum(0, 3, false);
ASSERT_EQ("EOF", Read());
ASSERT_EQ(3U, DroppedBytes());
ASSERT_EQ("OK", MatchError("unknown record type"));
}
TEST_P(LogTest, TruncatedTrailingRecordIsIgnored) {
Write("foo");
ShrinkSize(4); // Drop all payload as well as a header byte
ASSERT_EQ("EOF", Read());
// Truncated last record is ignored, not treated as an error
ASSERT_EQ(0U, DroppedBytes());
ASSERT_EQ("", ReportMessage());
}
TEST_P(LogTest, TruncatedTrailingRecordIsNotIgnored) {
if (allow_retry_read_) {
// If read retry is allowed, then truncated trailing record should not
// raise an error.
return;
}
Write("foo");
ShrinkSize(4); // Drop all payload as well as a header byte
ASSERT_EQ("EOF", Read(WALRecoveryMode::kAbsoluteConsistency));
// Truncated last record is ignored, not treated as an error
ASSERT_GT(DroppedBytes(), 0U);
ASSERT_EQ("OK", MatchError("Corruption: truncated header"));
}
TEST_P(LogTest, BadLength) {
if (allow_retry_read_) {
// If read retry is allowed, then we should not raise an error when the
// record length specified in header is longer than data currently
// available. It's possible that the body of the record is not written yet.
return;
}
bool recyclable_log = (std::get<0>(GetParam()) != 0);
int header_size = recyclable_log ? kRecyclableHeaderSize : kHeaderSize;
const int kPayloadSize = kBlockSize - header_size;
Write(BigString("bar", kPayloadSize));
Write("foo");
// Least significant size byte is stored in header[4].
IncrementByte(4, 1);
if (!recyclable_log) {
ASSERT_EQ("foo", Read());
ASSERT_EQ(kBlockSize, DroppedBytes());
ASSERT_EQ("OK", MatchError("bad record length"));
} else {
ASSERT_EQ("EOF", Read());
}
}
TEST_P(LogTest, BadLengthAtEndIsIgnored) {
if (allow_retry_read_) {
// If read retry is allowed, then we should not raise an error when the
// record length specified in header is longer than data currently
// available. It's possible that the body of the record is not written yet.
return;
}
Write("foo");
ShrinkSize(1);
ASSERT_EQ("EOF", Read());
ASSERT_EQ(0U, DroppedBytes());
ASSERT_EQ("", ReportMessage());
}
TEST_P(LogTest, BadLengthAtEndIsNotIgnored) {
if (allow_retry_read_) {
// If read retry is allowed, then we should not raise an error when the
// record length specified in header is longer than data currently
// available. It's possible that the body of the record is not written yet.
return;
}
Write("foo");
ShrinkSize(1);
ASSERT_EQ("EOF", Read(WALRecoveryMode::kAbsoluteConsistency));
ASSERT_GT(DroppedBytes(), 0U);
ASSERT_EQ("OK", MatchError("Corruption: truncated header"));
}
TEST_P(LogTest, ChecksumMismatch) {
Write("foooooo");
IncrementByte(0, 14);
ASSERT_EQ("EOF", Read());
bool recyclable_log = (std::get<0>(GetParam()) != 0);
if (!recyclable_log) {
ASSERT_EQ(14U, DroppedBytes());
ASSERT_EQ("OK", MatchError("checksum mismatch"));
} else {
ASSERT_EQ(0U, DroppedBytes());
ASSERT_EQ("", ReportMessage());
}
}
TEST_P(LogTest, UnexpectedMiddleType) {
Write("foo");
bool recyclable_log = (std::get<0>(GetParam()) != 0);
SetByte(6, static_cast<char>(recyclable_log ? kRecyclableMiddleType
: kMiddleType));
FixChecksum(0, 3, !!recyclable_log);
ASSERT_EQ("EOF", Read());
ASSERT_EQ(3U, DroppedBytes());
ASSERT_EQ("OK", MatchError("missing start"));
}
TEST_P(LogTest, UnexpectedLastType) {
Write("foo");
bool recyclable_log = (std::get<0>(GetParam()) != 0);
SetByte(6,
static_cast<char>(recyclable_log ? kRecyclableLastType : kLastType));
FixChecksum(0, 3, !!recyclable_log);
ASSERT_EQ("EOF", Read());
ASSERT_EQ(3U, DroppedBytes());
ASSERT_EQ("OK", MatchError("missing start"));
}
TEST_P(LogTest, UnexpectedFullType) {
Write("foo");
Write("bar");
bool recyclable_log = (std::get<0>(GetParam()) != 0);
SetByte(
6, static_cast<char>(recyclable_log ? kRecyclableFirstType : kFirstType));
FixChecksum(0, 3, !!recyclable_log);
ASSERT_EQ("bar", Read());
ASSERT_EQ("EOF", Read());
ASSERT_EQ(3U, DroppedBytes());
ASSERT_EQ("OK", MatchError("partial record without end"));
}
TEST_P(LogTest, UnexpectedFirstType) {
Write("foo");
Write(BigString("bar", 100000));
bool recyclable_log = (std::get<0>(GetParam()) != 0);
SetByte(
6, static_cast<char>(recyclable_log ? kRecyclableFirstType : kFirstType));
FixChecksum(0, 3, !!recyclable_log);
ASSERT_EQ(BigString("bar", 100000), Read());
ASSERT_EQ("EOF", Read());
ASSERT_EQ(3U, DroppedBytes());
ASSERT_EQ("OK", MatchError("partial record without end"));
}
TEST_P(LogTest, MissingLastIsIgnored) {
Write(BigString("bar", kBlockSize));
// Remove the LAST block, including header.
ShrinkSize(14);
ASSERT_EQ("EOF", Read());
ASSERT_EQ("", ReportMessage());
ASSERT_EQ(0U, DroppedBytes());
}
TEST_P(LogTest, MissingLastIsNotIgnored) {
if (allow_retry_read_) {
// If read retry is allowed, then truncated trailing record should not
// raise an error.
return;
}
Write(BigString("bar", kBlockSize));
// Remove the LAST block, including header.
ShrinkSize(14);
ASSERT_EQ("EOF", Read(WALRecoveryMode::kAbsoluteConsistency));
ASSERT_GT(DroppedBytes(), 0U);
ASSERT_EQ("OK", MatchError("Corruption: error reading trailing data"));
}
TEST_P(LogTest, PartialLastIsIgnored) {
Write(BigString("bar", kBlockSize));
// Cause a bad record length in the LAST block.
ShrinkSize(1);
ASSERT_EQ("EOF", Read());
ASSERT_EQ("", ReportMessage());
ASSERT_EQ(0U, DroppedBytes());
}
TEST_P(LogTest, PartialLastIsNotIgnored) {
if (allow_retry_read_) {
// If read retry is allowed, then truncated trailing record should not
// raise an error.
return;
}
Write(BigString("bar", kBlockSize));
// Cause a bad record length in the LAST block.
ShrinkSize(1);
ASSERT_EQ("EOF", Read(WALRecoveryMode::kAbsoluteConsistency));
ASSERT_GT(DroppedBytes(), 0U);
ASSERT_EQ("OK", MatchError(
"Corruption: truncated headerCorruption: "
"error reading trailing data"));
}
TEST_P(LogTest, ErrorJoinsRecords) {
// Consider two fragmented records:
// first(R1) last(R1) first(R2) last(R2)
// where the middle two fragments disappear. We do not want
// first(R1),last(R2) to get joined and returned as a valid record.
// Write records that span two blocks
Write(BigString("foo", kBlockSize));
Write(BigString("bar", kBlockSize));
Write("correct");
// Wipe the middle block
for (unsigned int offset = kBlockSize; offset < 2*kBlockSize; offset++) {
SetByte(offset, 'x');
}
bool recyclable_log = (std::get<0>(GetParam()) != 0);
if (!recyclable_log) {
ASSERT_EQ("correct", Read());
ASSERT_EQ("EOF", Read());
size_t dropped = DroppedBytes();
ASSERT_LE(dropped, 2 * kBlockSize + 100);
ASSERT_GE(dropped, 2 * kBlockSize);
} else {
ASSERT_EQ("EOF", Read());
}
}
TEST_P(LogTest, ClearEofSingleBlock) {
Write("foo");
Write("bar");
bool recyclable_log = (std::get<0>(GetParam()) != 0);
int header_size = recyclable_log ? kRecyclableHeaderSize : kHeaderSize;
ForceEOF(3 + header_size + 2);
ASSERT_EQ("foo", Read());
UnmarkEOF();
ASSERT_EQ("bar", Read());
ASSERT_TRUE(IsEOF());
ASSERT_EQ("EOF", Read());
Write("xxx");
UnmarkEOF();
ASSERT_EQ("xxx", Read());
ASSERT_TRUE(IsEOF());
}
TEST_P(LogTest, ClearEofMultiBlock) {
size_t num_full_blocks = 5;
bool recyclable_log = (std::get<0>(GetParam()) != 0);
int header_size = recyclable_log ? kRecyclableHeaderSize : kHeaderSize;
size_t n = (kBlockSize - header_size) * num_full_blocks + 25;
Write(BigString("foo", n));
Write(BigString("bar", n));
ForceEOF(n + num_full_blocks * header_size + header_size + 3);
ASSERT_EQ(BigString("foo", n), Read());
ASSERT_TRUE(IsEOF());
UnmarkEOF();
ASSERT_EQ(BigString("bar", n), Read());
ASSERT_TRUE(IsEOF());
Write(BigString("xxx", n));
UnmarkEOF();
ASSERT_EQ(BigString("xxx", n), Read());
ASSERT_TRUE(IsEOF());
}
TEST_P(LogTest, ClearEofError) {
// If an error occurs during Read() in UnmarkEOF(), the records contained
// in the buffer should be returned on subsequent calls of ReadRecord()
// until no more full records are left, whereafter ReadRecord() should return
// false to indicate that it cannot read any further.
Write("foo");
Write("bar");
UnmarkEOF();
ASSERT_EQ("foo", Read());
ASSERT_TRUE(IsEOF());
Write("xxx");
ForceError(0);
UnmarkEOF();
ASSERT_EQ("bar", Read());
ASSERT_EQ("EOF", Read());
}
TEST_P(LogTest, ClearEofError2) {
Write("foo");
Write("bar");
UnmarkEOF();
ASSERT_EQ("foo", Read());
Write("xxx");
ForceError(3);
UnmarkEOF();
ASSERT_EQ("bar", Read());
ASSERT_EQ("EOF", Read());
ASSERT_EQ(3U, DroppedBytes());
ASSERT_EQ("OK", MatchError("read error"));
}
TEST_P(LogTest, Recycle) {
bool recyclable_log = (std::get<0>(GetParam()) != 0);
if (!recyclable_log) {
return; // test is only valid for recycled logs
}
Write("foo");
Write("bar");
Write("baz");
Write("bif");
Write("blitz");
while (get_reader_contents()->size() < log::kBlockSize * 2) {
Write("xxxxxxxxxxxxxxxx");
}
std::unique_ptr<WritableFileWriter> dest_holder(test::GetWritableFileWriter(
new test::OverwritingStringSink(get_reader_contents()),
"" /* don't care */));
Writer recycle_writer(std::move(dest_holder), 123, true);
recycle_writer.AddRecord(Slice("foooo"));
recycle_writer.AddRecord(Slice("bar"));
ASSERT_GE(get_reader_contents()->size(), log::kBlockSize * 2);
ASSERT_EQ("foooo", Read());
ASSERT_EQ("bar", Read());
ASSERT_EQ("EOF", Read());
}
INSTANTIATE_TEST_CASE_P(bool, LogTest,
::testing::Values(std::make_tuple(0, false),
std::make_tuple(0, true),
std::make_tuple(1, false),
std::make_tuple(1, true)));
class RetriableLogTest : public ::testing::TestWithParam<int> {
private:
class ReportCollector : public Reader::Reporter {
public:
size_t dropped_bytes_;
std::string message_;
ReportCollector() : dropped_bytes_(0) {}
void Corruption(size_t bytes, const Status& status) override {
dropped_bytes_ += bytes;
message_.append(status.ToString());
}
};
Slice contents_;
std::unique_ptr<WritableFileWriter> dest_holder_;
std::unique_ptr<Writer> log_writer_;
Env* env_;
EnvOptions env_options_;
const std::string test_dir_;
const std::string log_file_;
std::unique_ptr<WritableFileWriter> writer_;
std::unique_ptr<SequentialFileReader> reader_;
ReportCollector report_;
std::unique_ptr<FragmentBufferedReader> log_reader_;
public:
RetriableLogTest()
: contents_(),
dest_holder_(nullptr),
log_writer_(nullptr),
env_(Env::Default()),
test_dir_(test::PerThreadDBPath("retriable_log_test")),
log_file_(test_dir_ + "/log"),
writer_(nullptr),
reader_(nullptr),
log_reader_(nullptr) {}
Status SetupTestEnv() {
dest_holder_.reset(test::GetWritableFileWriter(
new test::StringSink(&contents_), "" /* file name */));
assert(dest_holder_ != nullptr);
log_writer_.reset(new Writer(std::move(dest_holder_), 123, GetParam()));
assert(log_writer_ != nullptr);
Status s;
s = env_->CreateDirIfMissing(test_dir_);
std::unique_ptr<WritableFile> writable_file;
if (s.ok()) {
s = env_->NewWritableFile(log_file_, &writable_file, env_options_);
}
if (s.ok()) {
writer_.reset(new WritableFileWriter(std::move(writable_file), log_file_,
env_options_));
assert(writer_ != nullptr);
}
std::unique_ptr<SequentialFile> seq_file;
if (s.ok()) {
s = env_->NewSequentialFile(log_file_, &seq_file, env_options_);
}
if (s.ok()) {
reader_.reset(new SequentialFileReader(std::move(seq_file), log_file_));
assert(reader_ != nullptr);
log_reader_.reset(new FragmentBufferedReader(
nullptr, std::move(reader_), &report_, true /* checksum */,
123 /* log_number */));
assert(log_reader_ != nullptr);
}
return s;
}
std::string contents() {
auto file =
dynamic_cast<test::StringSink*>(log_writer_->file()->writable_file());
assert(file != nullptr);
return file->contents_;
}
void Encode(const std::string& msg) { log_writer_->AddRecord(Slice(msg)); }
void Write(const Slice& data) {
writer_->Append(data);
writer_->Sync(true);
}
bool TryRead(std::string* result) {
assert(result != nullptr);
result->clear();
std::string scratch;
Slice record;
bool r = log_reader_->ReadRecord(&record, &scratch);
if (r) {
result->assign(record.data(), record.size());
return true;
} else {
return false;
}
}
};
TEST_P(RetriableLogTest, TailLog_PartialHeader) {
ASSERT_OK(SetupTestEnv());
std::vector<int> remaining_bytes_in_last_record;
size_t header_size = GetParam() ? kRecyclableHeaderSize : kHeaderSize;
bool eof = false;
SyncPoint::GetInstance()->DisableProcessing();
SyncPoint::GetInstance()->LoadDependency(
{{"RetriableLogTest::TailLog:AfterPart1",
"RetriableLogTest::TailLog:BeforeReadRecord"},
{"FragmentBufferedLogReader::TryReadMore:FirstEOF",
"RetriableLogTest::TailLog:BeforePart2"}});
SyncPoint::GetInstance()->ClearAllCallBacks();
SyncPoint::GetInstance()->SetCallBack(
"FragmentBufferedLogReader::TryReadMore:FirstEOF",
[&](void* /*arg*/) { eof = true; });
SyncPoint::GetInstance()->EnableProcessing();
size_t delta = header_size - 1;
port::Thread log_writer_thread([&]() {
size_t old_sz = contents().size();
Encode("foo");
size_t new_sz = contents().size();
std::string part1 = contents().substr(old_sz, delta);
std::string part2 =
contents().substr(old_sz + delta, new_sz - old_sz - delta);
Write(Slice(part1));
TEST_SYNC_POINT("RetriableLogTest::TailLog:AfterPart1");
TEST_SYNC_POINT("RetriableLogTest::TailLog:BeforePart2");
Write(Slice(part2));
});
std::string record;
port::Thread log_reader_thread([&]() {
TEST_SYNC_POINT("RetriableLogTest::TailLog:BeforeReadRecord");
while (!TryRead(&record)) {
}
});
log_reader_thread.join();
log_writer_thread.join();
ASSERT_EQ("foo", record);
ASSERT_TRUE(eof);
}
TEST_P(RetriableLogTest, TailLog_FullHeader) {
ASSERT_OK(SetupTestEnv());
std::vector<int> remaining_bytes_in_last_record;
size_t header_size = GetParam() ? kRecyclableHeaderSize : kHeaderSize;
bool eof = false;
SyncPoint::GetInstance()->DisableProcessing();
SyncPoint::GetInstance()->LoadDependency(
{{"RetriableLogTest::TailLog:AfterPart1",
"RetriableLogTest::TailLog:BeforeReadRecord"},
{"FragmentBufferedLogReader::TryReadMore:FirstEOF",
"RetriableLogTest::TailLog:BeforePart2"}});
SyncPoint::GetInstance()->ClearAllCallBacks();
SyncPoint::GetInstance()->SetCallBack(
"FragmentBufferedLogReader::TryReadMore:FirstEOF",
[&](void* /*arg*/) { eof = true; });
SyncPoint::GetInstance()->EnableProcessing();
size_t delta = header_size + 1;
port::Thread log_writer_thread([&]() {
size_t old_sz = contents().size();
Encode("foo");
size_t new_sz = contents().size();
std::string part1 = contents().substr(old_sz, delta);
std::string part2 =
contents().substr(old_sz + delta, new_sz - old_sz - delta);
Write(Slice(part1));
TEST_SYNC_POINT("RetriableLogTest::TailLog:AfterPart1");
TEST_SYNC_POINT("RetriableLogTest::TailLog:BeforePart2");
Write(Slice(part2));
ASSERT_TRUE(eof);
});
std::string record;
port::Thread log_reader_thread([&]() {
TEST_SYNC_POINT("RetriableLogTest::TailLog:BeforeReadRecord");
while (!TryRead(&record)) {
}
});
log_reader_thread.join();
log_writer_thread.join();
ASSERT_EQ("foo", record);
}
TEST_P(RetriableLogTest, NonBlockingReadFullRecord) {
// Clear all sync point callbacks even if this test does not use sync point.
// It is necessary, otherwise the execute of this test may hit a sync point
// with which a callback is registered. The registered callback may access
// some dead variable, causing segfault.
SyncPoint::GetInstance()->DisableProcessing();
SyncPoint::GetInstance()->ClearAllCallBacks();
ASSERT_OK(SetupTestEnv());
size_t header_size = GetParam() ? kRecyclableHeaderSize : kHeaderSize;
size_t delta = header_size - 1;
size_t old_sz = contents().size();
Encode("foo-bar");
size_t new_sz = contents().size();
std::string part1 = contents().substr(old_sz, delta);
std::string part2 =
contents().substr(old_sz + delta, new_sz - old_sz - delta);
Write(Slice(part1));
std::string record;
ASSERT_FALSE(TryRead(&record));
ASSERT_TRUE(record.empty());
Write(Slice(part2));
ASSERT_TRUE(TryRead(&record));
ASSERT_EQ("foo-bar", record);
}
INSTANTIATE_TEST_CASE_P(bool, RetriableLogTest, ::testing::Values(0, 2));
} // namespace log
} // namespace rocksdb
int main(int argc, char** argv) {
::testing::InitGoogleTest(&argc, argv);
return RUN_ALL_TESTS();
}