Revision 0d4a2b733070a1bd52f981313f9e17f126701407 authored by Yi Wu on 04 August 2017, 20:09:56 UTC, committed by Facebook Github Bot on 04 August 2017, 20:12:07 UTC
Summary: The FsyncFiles background job call Fsync() periodically for blob files. However it can access WritableFileWriter concurrently with a Put() or Write(). And WritableFileWriter does not support concurrent access. It will lead to WritableFileWriter buffer being flush with same content twice, and blob file end up corrupted. Fixing by simply let FsyncFiles hold write_mutex_. Closes https://github.com/facebook/rocksdb/pull/2685 Differential Revision: D5561908 Pulled By: yiwu-arbug fbshipit-source-id: f0bb5bcab0e05694e053b8c49eab43640721e872
1 parent 627c9f1
dynamic_bloom_test.cc
// 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).
#ifndef GFLAGS
#include <cstdio>
int main() {
fprintf(stderr, "Please install gflags to run this test... Skipping...\n");
return 0;
}
#else
#ifndef __STDC_FORMAT_MACROS
#define __STDC_FORMAT_MACROS
#endif
#include <gflags/gflags.h>
#include <inttypes.h>
#include <algorithm>
#include <atomic>
#include <functional>
#include <memory>
#include <thread>
#include <vector>
#include "dynamic_bloom.h"
#include "port/port.h"
#include "util/arena.h"
#include "util/logging.h"
#include "util/testharness.h"
#include "util/testutil.h"
#include "util/stop_watch.h"
using GFLAGS::ParseCommandLineFlags;
DEFINE_int32(bits_per_key, 10, "");
DEFINE_int32(num_probes, 6, "");
DEFINE_bool(enable_perf, false, "");
namespace rocksdb {
static Slice Key(uint64_t i, char* buffer) {
memcpy(buffer, &i, sizeof(i));
return Slice(buffer, sizeof(i));
}
class DynamicBloomTest : public testing::Test {};
TEST_F(DynamicBloomTest, EmptyFilter) {
Arena arena;
DynamicBloom bloom1(&arena, 100, 0, 2);
ASSERT_TRUE(!bloom1.MayContain("hello"));
ASSERT_TRUE(!bloom1.MayContain("world"));
DynamicBloom bloom2(&arena, CACHE_LINE_SIZE * 8 * 2 - 1, 1, 2);
ASSERT_TRUE(!bloom2.MayContain("hello"));
ASSERT_TRUE(!bloom2.MayContain("world"));
}
TEST_F(DynamicBloomTest, Small) {
Arena arena;
DynamicBloom bloom1(&arena, 100, 0, 2);
bloom1.Add("hello");
bloom1.Add("world");
ASSERT_TRUE(bloom1.MayContain("hello"));
ASSERT_TRUE(bloom1.MayContain("world"));
ASSERT_TRUE(!bloom1.MayContain("x"));
ASSERT_TRUE(!bloom1.MayContain("foo"));
DynamicBloom bloom2(&arena, CACHE_LINE_SIZE * 8 * 2 - 1, 1, 2);
bloom2.Add("hello");
bloom2.Add("world");
ASSERT_TRUE(bloom2.MayContain("hello"));
ASSERT_TRUE(bloom2.MayContain("world"));
ASSERT_TRUE(!bloom2.MayContain("x"));
ASSERT_TRUE(!bloom2.MayContain("foo"));
}
TEST_F(DynamicBloomTest, SmallConcurrentAdd) {
Arena arena;
DynamicBloom bloom1(&arena, 100, 0, 2);
bloom1.AddConcurrently("hello");
bloom1.AddConcurrently("world");
ASSERT_TRUE(bloom1.MayContain("hello"));
ASSERT_TRUE(bloom1.MayContain("world"));
ASSERT_TRUE(!bloom1.MayContain("x"));
ASSERT_TRUE(!bloom1.MayContain("foo"));
DynamicBloom bloom2(&arena, CACHE_LINE_SIZE * 8 * 2 - 1, 1, 2);
bloom2.AddConcurrently("hello");
bloom2.AddConcurrently("world");
ASSERT_TRUE(bloom2.MayContain("hello"));
ASSERT_TRUE(bloom2.MayContain("world"));
ASSERT_TRUE(!bloom2.MayContain("x"));
ASSERT_TRUE(!bloom2.MayContain("foo"));
}
static uint32_t NextNum(uint32_t num) {
if (num < 10) {
num += 1;
} else if (num < 100) {
num += 10;
} else if (num < 1000) {
num += 100;
} else {
num += 1000;
}
return num;
}
TEST_F(DynamicBloomTest, VaryingLengths) {
char buffer[sizeof(uint64_t)];
// Count number of filters that significantly exceed the false positive rate
int mediocre_filters = 0;
int good_filters = 0;
uint32_t num_probes = static_cast<uint32_t>(FLAGS_num_probes);
fprintf(stderr, "bits_per_key: %d num_probes: %d\n", FLAGS_bits_per_key,
num_probes);
for (uint32_t enable_locality = 0; enable_locality < 2; ++enable_locality) {
for (uint32_t num = 1; num <= 10000; num = NextNum(num)) {
uint32_t bloom_bits = 0;
Arena arena;
if (enable_locality == 0) {
bloom_bits = std::max(num * FLAGS_bits_per_key, 64U);
} else {
bloom_bits = std::max(num * FLAGS_bits_per_key,
enable_locality * CACHE_LINE_SIZE * 8);
}
DynamicBloom bloom(&arena, bloom_bits, enable_locality, num_probes);
for (uint64_t i = 0; i < num; i++) {
bloom.Add(Key(i, buffer));
ASSERT_TRUE(bloom.MayContain(Key(i, buffer)));
}
// All added keys must match
for (uint64_t i = 0; i < num; i++) {
ASSERT_TRUE(bloom.MayContain(Key(i, buffer))) << "Num " << num
<< "; key " << i;
}
// Check false positive rate
int result = 0;
for (uint64_t i = 0; i < 10000; i++) {
if (bloom.MayContain(Key(i + 1000000000, buffer))) {
result++;
}
}
double rate = result / 10000.0;
fprintf(stderr,
"False positives: %5.2f%% @ num = %6u, bloom_bits = %6u, "
"enable locality?%u\n",
rate * 100.0, num, bloom_bits, enable_locality);
if (rate > 0.0125)
mediocre_filters++; // Allowed, but not too often
else
good_filters++;
}
fprintf(stderr, "Filters: %d good, %d mediocre\n", good_filters,
mediocre_filters);
ASSERT_LE(mediocre_filters, good_filters / 5);
}
}
TEST_F(DynamicBloomTest, perf) {
StopWatchNano timer(Env::Default());
uint32_t num_probes = static_cast<uint32_t>(FLAGS_num_probes);
if (!FLAGS_enable_perf) {
return;
}
for (uint32_t m = 1; m <= 8; ++m) {
Arena arena;
const uint32_t num_keys = m * 8 * 1024 * 1024;
fprintf(stderr, "testing %" PRIu32 "M keys\n", m * 8);
DynamicBloom std_bloom(&arena, num_keys * 10, 0, num_probes);
timer.Start();
for (uint64_t i = 1; i <= num_keys; ++i) {
std_bloom.Add(Slice(reinterpret_cast<const char*>(&i), 8));
}
uint64_t elapsed = timer.ElapsedNanos();
fprintf(stderr, "standard bloom, avg add latency %" PRIu64 "\n",
elapsed / num_keys);
uint32_t count = 0;
timer.Start();
for (uint64_t i = 1; i <= num_keys; ++i) {
if (std_bloom.MayContain(Slice(reinterpret_cast<const char*>(&i), 8))) {
++count;
}
}
ASSERT_EQ(count, num_keys);
elapsed = timer.ElapsedNanos();
assert(count > 0);
fprintf(stderr, "standard bloom, avg query latency %" PRIu64 "\n",
elapsed / count);
// Locality enabled version
DynamicBloom blocked_bloom(&arena, num_keys * 10, 1, num_probes);
timer.Start();
for (uint64_t i = 1; i <= num_keys; ++i) {
blocked_bloom.Add(Slice(reinterpret_cast<const char*>(&i), 8));
}
elapsed = timer.ElapsedNanos();
fprintf(stderr,
"blocked bloom(enable locality), avg add latency %" PRIu64 "\n",
elapsed / num_keys);
count = 0;
timer.Start();
for (uint64_t i = 1; i <= num_keys; ++i) {
if (blocked_bloom.MayContain(
Slice(reinterpret_cast<const char*>(&i), 8))) {
++count;
}
}
elapsed = timer.ElapsedNanos();
assert(count > 0);
fprintf(stderr,
"blocked bloom(enable locality), avg query latency %" PRIu64 "\n",
elapsed / count);
ASSERT_TRUE(count == num_keys);
}
}
TEST_F(DynamicBloomTest, concurrent_with_perf) {
StopWatchNano timer(Env::Default());
uint32_t num_probes = static_cast<uint32_t>(FLAGS_num_probes);
uint32_t m_limit = FLAGS_enable_perf ? 8 : 1;
uint32_t locality_limit = FLAGS_enable_perf ? 1 : 0;
uint32_t num_threads = 4;
std::vector<port::Thread> threads;
for (uint32_t m = 1; m <= m_limit; ++m) {
for (uint32_t locality = 0; locality <= locality_limit; ++locality) {
Arena arena;
const uint32_t num_keys = m * 8 * 1024 * 1024;
fprintf(stderr, "testing %" PRIu32 "M keys with %" PRIu32 " locality\n",
m * 8, locality);
DynamicBloom std_bloom(&arena, num_keys * 10, locality, num_probes);
timer.Start();
std::function<void(size_t)> adder = [&](size_t t) {
for (uint64_t i = 1 + t; i <= num_keys; i += num_threads) {
std_bloom.AddConcurrently(
Slice(reinterpret_cast<const char*>(&i), 8));
}
};
for (size_t t = 0; t < num_threads; ++t) {
threads.emplace_back(adder, t);
}
while (threads.size() > 0) {
threads.back().join();
threads.pop_back();
}
uint64_t elapsed = timer.ElapsedNanos();
fprintf(stderr, "standard bloom, avg parallel add latency %" PRIu64
" nanos/key\n",
elapsed / num_keys);
timer.Start();
std::function<void(size_t)> hitter = [&](size_t t) {
for (uint64_t i = 1 + t; i <= num_keys; i += num_threads) {
bool f =
std_bloom.MayContain(Slice(reinterpret_cast<const char*>(&i), 8));
ASSERT_TRUE(f);
}
};
for (size_t t = 0; t < num_threads; ++t) {
threads.emplace_back(hitter, t);
}
while (threads.size() > 0) {
threads.back().join();
threads.pop_back();
}
elapsed = timer.ElapsedNanos();
fprintf(stderr, "standard bloom, avg parallel hit latency %" PRIu64
" nanos/key\n",
elapsed / num_keys);
timer.Start();
std::atomic<uint32_t> false_positives(0);
std::function<void(size_t)> misser = [&](size_t t) {
for (uint64_t i = num_keys + 1 + t; i <= 2 * num_keys;
i += num_threads) {
bool f =
std_bloom.MayContain(Slice(reinterpret_cast<const char*>(&i), 8));
if (f) {
++false_positives;
}
}
};
for (size_t t = 0; t < num_threads; ++t) {
threads.emplace_back(misser, t);
}
while (threads.size() > 0) {
threads.back().join();
threads.pop_back();
}
elapsed = timer.ElapsedNanos();
fprintf(stderr, "standard bloom, avg parallel miss latency %" PRIu64
" nanos/key, %f%% false positive rate\n",
elapsed / num_keys, false_positives.load() * 100.0 / num_keys);
}
}
}
} // namespace rocksdb
int main(int argc, char** argv) {
::testing::InitGoogleTest(&argc, argv);
ParseCommandLineFlags(&argc, &argv, true);
return RUN_ALL_TESTS();
}
#endif // GFLAGS
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