rocksdb/file/random_access_file_reader_test.cc
mrambacher 12f1137355 Add a SystemClock class to capture the time functions of an Env (#7858)
Summary:
Introduces and uses a SystemClock class to RocksDB.  This class contains the time-related functions of an Env and these functions can be redirected from the Env to the SystemClock.

Many of the places that used an Env (Timer, PerfStepTimer, RepeatableThread, RateLimiter, WriteController) for time-related functions have been changed to use SystemClock instead.  There are likely more places that can be changed, but this is a start to show what can/should be done.  Over time it would be nice to migrate most (if not all) of the uses of the time functions from the Env to the SystemClock.

There are several Env classes that implement these functions.  Most of these have not been converted yet to SystemClock implementations; that will come in a subsequent PR.  It would be good to unify many of the Mock Timer implementations, so that they behave similarly and be tested similarly (some override Sleep, some use a MockSleep, etc).

Additionally, this change will allow new methods to be introduced to the SystemClock (like https://github.com/facebook/rocksdb/issues/7101 WaitFor) in a consistent manner across a smaller number of classes.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7858

Reviewed By: pdillinger

Differential Revision: D26006406

Pulled By: mrambacher

fbshipit-source-id: ed10a8abbdab7ff2e23d69d85bd25b3e7e899e90
2021-01-25 22:09:11 -08:00

484 lines
13 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).
#include "file/random_access_file_reader.h"
#include <algorithm>
#include "file/file_util.h"
#include "port/port.h"
#include "port/stack_trace.h"
#include "rocksdb/file_system.h"
#include "test_util/sync_point.h"
#include "test_util/testharness.h"
#include "test_util/testutil.h"
#include "util/random.h"
namespace ROCKSDB_NAMESPACE {
class RandomAccessFileReaderTest : public testing::Test {
public:
void SetUp() override {
SetupSyncPointsToMockDirectIO();
env_ = Env::Default();
fs_ = FileSystem::Default();
test_dir_ = test::PerThreadDBPath("random_access_file_reader_test");
ASSERT_OK(fs_->CreateDir(test_dir_, IOOptions(), nullptr));
}
void TearDown() override { EXPECT_OK(DestroyDir(env_, test_dir_)); }
void Write(const std::string& fname, const std::string& content) {
std::unique_ptr<FSWritableFile> f;
ASSERT_OK(fs_->NewWritableFile(Path(fname), FileOptions(), &f, nullptr));
ASSERT_OK(f->Append(content, IOOptions(), nullptr));
ASSERT_OK(f->Close(IOOptions(), nullptr));
}
void Read(const std::string& fname, const FileOptions& opts,
std::unique_ptr<RandomAccessFileReader>* reader) {
std::string fpath = Path(fname);
std::unique_ptr<FSRandomAccessFile> f;
ASSERT_OK(fs_->NewRandomAccessFile(fpath, opts, &f, nullptr));
(*reader).reset(new RandomAccessFileReader(std::move(f), fpath,
env_->GetSystemClock()));
}
void AssertResult(const std::string& content,
const std::vector<FSReadRequest>& reqs) {
for (const auto& r : reqs) {
ASSERT_OK(r.status);
ASSERT_EQ(r.len, r.result.size());
ASSERT_EQ(content.substr(r.offset, r.len), r.result.ToString());
}
}
private:
Env* env_;
std::shared_ptr<FileSystem> fs_;
std::string test_dir_;
std::string Path(const std::string& fname) {
return test_dir_ + "/" + fname;
}
};
// Skip the following tests in lite mode since direct I/O is unsupported.
#ifndef ROCKSDB_LITE
TEST_F(RandomAccessFileReaderTest, ReadDirectIO) {
std::string fname = "read-direct-io";
Random rand(0);
std::string content = rand.RandomString(kDefaultPageSize);
Write(fname, content);
FileOptions opts;
opts.use_direct_reads = true;
std::unique_ptr<RandomAccessFileReader> r;
Read(fname, opts, &r);
ASSERT_TRUE(r->use_direct_io());
const size_t page_size = r->file()->GetRequiredBufferAlignment();
size_t offset = page_size / 2;
size_t len = page_size / 3;
Slice result;
AlignedBuf buf;
for (bool for_compaction : {true, false}) {
ASSERT_OK(r->Read(IOOptions(), offset, len, &result, nullptr, &buf,
for_compaction));
ASSERT_EQ(result.ToString(), content.substr(offset, len));
}
}
TEST_F(RandomAccessFileReaderTest, MultiReadDirectIO) {
std::vector<FSReadRequest> aligned_reqs;
ROCKSDB_NAMESPACE::SyncPoint::GetInstance()->SetCallBack(
"RandomAccessFileReader::MultiRead:AlignedReqs", [&](void* reqs) {
// Copy reqs, since it's allocated on stack inside MultiRead, which will
// be deallocated after MultiRead returns.
aligned_reqs = *reinterpret_cast<std::vector<FSReadRequest>*>(reqs);
});
ROCKSDB_NAMESPACE::SyncPoint::GetInstance()->EnableProcessing();
// Creates a file with 3 pages.
std::string fname = "multi-read-direct-io";
Random rand(0);
std::string content = rand.RandomString(3 * kDefaultPageSize);
Write(fname, content);
FileOptions opts;
opts.use_direct_reads = true;
std::unique_ptr<RandomAccessFileReader> r;
Read(fname, opts, &r);
ASSERT_TRUE(r->use_direct_io());
const size_t page_size = r->file()->GetRequiredBufferAlignment();
{
// Reads 2 blocks in the 1st page.
// The results should be SharedSlices of the same underlying buffer.
//
// Illustration (each x is a 1/4 page)
// First page: xxxx
// 1st block: x
// 2nd block: xx
FSReadRequest r0;
r0.offset = 0;
r0.len = page_size / 4;
r0.scratch = nullptr;
FSReadRequest r1;
r1.offset = page_size / 2;
r1.len = page_size / 2;
r1.scratch = nullptr;
std::vector<FSReadRequest> reqs;
reqs.push_back(std::move(r0));
reqs.push_back(std::move(r1));
AlignedBuf aligned_buf;
ASSERT_OK(
r->MultiRead(IOOptions(), reqs.data(), reqs.size(), &aligned_buf));
AssertResult(content, reqs);
// Reads the first page internally.
ASSERT_EQ(aligned_reqs.size(), 1);
const FSReadRequest& aligned_r = aligned_reqs[0];
ASSERT_OK(aligned_r.status);
ASSERT_EQ(aligned_r.offset, 0);
ASSERT_EQ(aligned_r.len, page_size);
}
{
// Reads 3 blocks:
// 1st block in the 1st page;
// 2nd block from the middle of the 1st page to the middle of the 2nd page;
// 3rd block in the 2nd page.
// The results should be SharedSlices of the same underlying buffer.
//
// Illustration (each x is a 1/4 page)
// 2 pages: xxxxxxxx
// 1st block: x
// 2nd block: xxxx
// 3rd block: x
FSReadRequest r0;
r0.offset = 0;
r0.len = page_size / 4;
r0.scratch = nullptr;
FSReadRequest r1;
r1.offset = page_size / 2;
r1.len = page_size;
r1.scratch = nullptr;
FSReadRequest r2;
r2.offset = 2 * page_size - page_size / 4;
r2.len = page_size / 4;
r2.scratch = nullptr;
std::vector<FSReadRequest> reqs;
reqs.push_back(std::move(r0));
reqs.push_back(std::move(r1));
reqs.push_back(std::move(r2));
AlignedBuf aligned_buf;
ASSERT_OK(
r->MultiRead(IOOptions(), reqs.data(), reqs.size(), &aligned_buf));
AssertResult(content, reqs);
// Reads the first two pages in one request internally.
ASSERT_EQ(aligned_reqs.size(), 1);
const FSReadRequest& aligned_r = aligned_reqs[0];
ASSERT_OK(aligned_r.status);
ASSERT_EQ(aligned_r.offset, 0);
ASSERT_EQ(aligned_r.len, 2 * page_size);
}
{
// Reads 3 blocks:
// 1st block in the middle of the 1st page;
// 2nd block in the middle of the 2nd page;
// 3rd block in the middle of the 3rd page.
// The results should be SharedSlices of the same underlying buffer.
//
// Illustration (each x is a 1/4 page)
// 3 pages: xxxxxxxxxxxx
// 1st block: xx
// 2nd block: xx
// 3rd block: xx
FSReadRequest r0;
r0.offset = page_size / 4;
r0.len = page_size / 2;
r0.scratch = nullptr;
FSReadRequest r1;
r1.offset = page_size + page_size / 4;
r1.len = page_size / 2;
r1.scratch = nullptr;
FSReadRequest r2;
r2.offset = 2 * page_size + page_size / 4;
r2.len = page_size / 2;
r2.scratch = nullptr;
std::vector<FSReadRequest> reqs;
reqs.push_back(std::move(r0));
reqs.push_back(std::move(r1));
reqs.push_back(std::move(r2));
AlignedBuf aligned_buf;
ASSERT_OK(
r->MultiRead(IOOptions(), reqs.data(), reqs.size(), &aligned_buf));
AssertResult(content, reqs);
// Reads the first 3 pages in one request internally.
ASSERT_EQ(aligned_reqs.size(), 1);
const FSReadRequest& aligned_r = aligned_reqs[0];
ASSERT_OK(aligned_r.status);
ASSERT_EQ(aligned_r.offset, 0);
ASSERT_EQ(aligned_r.len, 3 * page_size);
}
{
// Reads 2 blocks:
// 1st block in the middle of the 1st page;
// 2nd block in the middle of the 3rd page.
// The results are two different buffers.
//
// Illustration (each x is a 1/4 page)
// 3 pages: xxxxxxxxxxxx
// 1st block: xx
// 2nd block: xx
FSReadRequest r0;
r0.offset = page_size / 4;
r0.len = page_size / 2;
r0.scratch = nullptr;
FSReadRequest r1;
r1.offset = 2 * page_size + page_size / 4;
r1.len = page_size / 2;
r1.scratch = nullptr;
std::vector<FSReadRequest> reqs;
reqs.push_back(std::move(r0));
reqs.push_back(std::move(r1));
AlignedBuf aligned_buf;
ASSERT_OK(
r->MultiRead(IOOptions(), reqs.data(), reqs.size(), &aligned_buf));
AssertResult(content, reqs);
// Reads the 1st and 3rd pages in two requests internally.
ASSERT_EQ(aligned_reqs.size(), 2);
const FSReadRequest& aligned_r0 = aligned_reqs[0];
const FSReadRequest& aligned_r1 = aligned_reqs[1];
ASSERT_OK(aligned_r0.status);
ASSERT_EQ(aligned_r0.offset, 0);
ASSERT_EQ(aligned_r0.len, page_size);
ASSERT_OK(aligned_r1.status);
ASSERT_EQ(aligned_r1.offset, 2 * page_size);
ASSERT_EQ(aligned_r1.len, page_size);
}
ROCKSDB_NAMESPACE::SyncPoint::GetInstance()->DisableProcessing();
ROCKSDB_NAMESPACE::SyncPoint::GetInstance()->ClearAllCallBacks();
}
#endif // ROCKSDB_LITE
TEST(FSReadRequest, Align) {
FSReadRequest r;
r.offset = 2000;
r.len = 2000;
r.scratch = nullptr;
ASSERT_OK(r.status);
FSReadRequest aligned_r = Align(r, 1024);
ASSERT_OK(r.status);
ASSERT_OK(aligned_r.status);
ASSERT_EQ(aligned_r.offset, 1024);
ASSERT_EQ(aligned_r.len, 3072);
}
TEST(FSReadRequest, TryMerge) {
// reverse means merging dest into src.
for (bool reverse : {true, false}) {
{
// dest: [ ]
// src: [ ]
FSReadRequest dest;
dest.offset = 0;
dest.len = 10;
dest.scratch = nullptr;
ASSERT_OK(dest.status);
FSReadRequest src;
src.offset = 15;
src.len = 10;
src.scratch = nullptr;
ASSERT_OK(src.status);
if (reverse) {
std::swap(dest, src);
}
ASSERT_FALSE(TryMerge(&dest, src));
ASSERT_OK(dest.status);
ASSERT_OK(src.status);
}
{
// dest: [ ]
// src: [ ]
FSReadRequest dest;
dest.offset = 0;
dest.len = 10;
dest.scratch = nullptr;
ASSERT_OK(dest.status);
FSReadRequest src;
src.offset = 10;
src.len = 10;
src.scratch = nullptr;
ASSERT_OK(src.status);
if (reverse) {
std::swap(dest, src);
}
ASSERT_TRUE(TryMerge(&dest, src));
ASSERT_EQ(dest.offset, 0);
ASSERT_EQ(dest.len, 20);
ASSERT_OK(dest.status);
ASSERT_OK(src.status);
}
{
// dest: [ ]
// src: [ ]
FSReadRequest dest;
dest.offset = 0;
dest.len = 10;
dest.scratch = nullptr;
ASSERT_OK(dest.status);
FSReadRequest src;
src.offset = 5;
src.len = 10;
src.scratch = nullptr;
ASSERT_OK(src.status);
if (reverse) {
std::swap(dest, src);
}
ASSERT_TRUE(TryMerge(&dest, src));
ASSERT_EQ(dest.offset, 0);
ASSERT_EQ(dest.len, 15);
ASSERT_OK(dest.status);
ASSERT_OK(src.status);
}
{
// dest: [ ]
// src: [ ]
FSReadRequest dest;
dest.offset = 0;
dest.len = 10;
dest.scratch = nullptr;
ASSERT_OK(dest.status);
FSReadRequest src;
src.offset = 5;
src.len = 5;
src.scratch = nullptr;
ASSERT_OK(src.status);
if (reverse) {
std::swap(dest, src);
}
ASSERT_TRUE(TryMerge(&dest, src));
ASSERT_EQ(dest.offset, 0);
ASSERT_EQ(dest.len, 10);
ASSERT_OK(dest.status);
ASSERT_OK(src.status);
}
{
// dest: [ ]
// src: [ ]
FSReadRequest dest;
dest.offset = 0;
dest.len = 10;
dest.scratch = nullptr;
ASSERT_OK(dest.status);
FSReadRequest src;
src.offset = 5;
src.len = 1;
src.scratch = nullptr;
ASSERT_OK(src.status);
if (reverse) std::swap(dest, src);
ASSERT_TRUE(TryMerge(&dest, src));
ASSERT_EQ(dest.offset, 0);
ASSERT_EQ(dest.len, 10);
ASSERT_OK(dest.status);
ASSERT_OK(src.status);
}
{
// dest: [ ]
// src: [ ]
FSReadRequest dest;
dest.offset = 0;
dest.len = 10;
dest.scratch = nullptr;
ASSERT_OK(dest.status);
FSReadRequest src;
src.offset = 0;
src.len = 10;
src.scratch = nullptr;
ASSERT_OK(src.status);
if (reverse) std::swap(dest, src);
ASSERT_TRUE(TryMerge(&dest, src));
ASSERT_EQ(dest.offset, 0);
ASSERT_EQ(dest.len, 10);
ASSERT_OK(dest.status);
ASSERT_OK(src.status);
}
{
// dest: [ ]
// src: [ ]
FSReadRequest dest;
dest.offset = 0;
dest.len = 10;
dest.scratch = nullptr;
ASSERT_OK(dest.status);
FSReadRequest src;
src.offset = 0;
src.len = 5;
src.scratch = nullptr;
ASSERT_OK(src.status);
if (reverse) std::swap(dest, src);
ASSERT_TRUE(TryMerge(&dest, src));
ASSERT_EQ(dest.offset, 0);
ASSERT_EQ(dest.len, 10);
ASSERT_OK(dest.status);
ASSERT_OK(src.status);
}
}
}
} // namespace ROCKSDB_NAMESPACE
int main(int argc, char** argv) {
ROCKSDB_NAMESPACE::port::InstallStackTraceHandler();
::testing::InitGoogleTest(&argc, argv);
return RUN_ALL_TESTS();
}