rocksdb/util/file_reader_writer_test.cc
Siying Dong 3dbf4ba220 RangeSync not to sync last 1MB of the file
Summary:
From other ones' investigation:

"sync_file_range() behavior highly depends on kernel version and filesystem.

xfs does neighbor page flushing outside of the specified ranges. For example, sync_file_range(fd, 8192, 16384) does not only trigger flushing page #3 to #4, but also flushing many more dirty pages (i.e. up to page#16)... Ranges of the sync_file_range() should be far enough from write() offset (at least 1MB)."

Test Plan: make all check

Reviewers: igor, rven, kradhakrishnan, yhchiang, IslamAbdelRahman, anthony

Reviewed By: anthony

Subscribers: yoshinorim, MarkCallaghan, sumeet, domas, dhruba, leveldb, ljin

Differential Revision: https://reviews.facebook.net/D15807
2015-07-21 16:22:40 -07:00

90 lines
2.8 KiB
C++

// Copyright (c) 2013, Facebook, Inc. All rights reserved.
// This source code is licensed under the BSD-style license found in the
// LICENSE file in the root directory of this source tree. An additional grant
// of patent rights can be found in the PATENTS file in the same directory.
//
#include <vector>
#include "util/file_reader_writer.h"
#include "util/random.h"
#include "util/testharness.h"
namespace rocksdb {
class WritableFileWriterTest : public testing::Test {};
const uint32_t kMb = 1 << 20;
TEST_F(WritableFileWriterTest, RangeSync) {
class FakeWF : public WritableFile {
public:
explicit FakeWF() : size_(0), last_synced_(0) {}
~FakeWF() {}
Status Append(const Slice& data) override {
size_ += data.size();
return Status::OK();
}
Status Close() override {
EXPECT_GE(size_, last_synced_ + kMb);
EXPECT_LT(size_, last_synced_ + 2 * kMb);
// Make sure random writes generated enough writes.
EXPECT_GT(size_, 10 * kMb);
return Status::OK();
}
Status Flush() override { return Status::OK(); }
Status Sync() override { return Status::OK(); }
Status Fsync() override { return Status::OK(); }
void SetIOPriority(Env::IOPriority pri) override {}
uint64_t GetFileSize() override { return size_; }
void GetPreallocationStatus(size_t* block_size,
size_t* last_allocated_block) override {}
size_t GetUniqueId(char* id, size_t max_size) const override { return 0; }
Status InvalidateCache(size_t offset, size_t length) override {
return Status::OK();
}
protected:
Status Allocate(off_t offset, off_t len) override { return Status::OK(); }
Status RangeSync(off_t offset, off_t nbytes) override {
EXPECT_EQ(offset % 4096, 0u);
EXPECT_EQ(nbytes % 4096, 0u);
EXPECT_EQ(offset, last_synced_);
last_synced_ = offset + nbytes;
EXPECT_GE(size_, last_synced_ + kMb);
if (size_ > 2 * kMb) {
EXPECT_LT(size_, last_synced_ + 2 * kMb);
}
return Status::OK();
}
uint64_t size_;
uint64_t last_synced_;
};
EnvOptions env_options;
env_options.bytes_per_sync = kMb;
unique_ptr<FakeWF> wf(new FakeWF);
unique_ptr<WritableFileWriter> writer(
new WritableFileWriter(std::move(wf), env_options));
Random r(301);
std::unique_ptr<char[]> large_buf(new char[10 * kMb]);
for (int i = 0; i < 1000; i++) {
int skew_limit = (i < 700) ? 10 : 15;
uint32_t num = r.Skewed(skew_limit) * 100 + r.Uniform(100);
writer->Append(Slice(large_buf.get(), num));
// Flush in a chance of 1/10.
if (r.Uniform(10) == 0) {
writer->Flush();
}
}
writer->Close();
}
} // namespace rocksdb
int main(int argc, char** argv) {
::testing::InitGoogleTest(&argc, argv);
return RUN_ALL_TESTS();
}