perf_context.get_from_output_files_time is set for MultiGet() and ReadOnly DB too.

Summary: perf_context.get_from_output_files_time is now only set writable DB's DB::Get(). Extend it to MultiGet() and read only DB.

Test Plan:
make all check
Fix perf_context_test and extend it to cover MultiGet(), as long as read-only DB. Run it and watch the results

Reviewers: ljin, yhchiang, igor

Reviewed By: igor

Subscribers: rven, leveldb

Differential Revision: https://reviews.facebook.net/D24207
This commit is contained in:
sdong 2014-10-02 17:02:30 -07:00
parent c1273533bd
commit f4086a88b4
4 changed files with 182 additions and 18 deletions

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@ -154,7 +154,7 @@ TOOLS = \
options_test \
blob_store_bench
PROGRAMS = db_bench signal_test table_reader_bench log_and_apply_bench cache_bench $(TOOLS)
PROGRAMS = db_bench signal_test table_reader_bench log_and_apply_bench cache_bench perf_context_test $(TOOLS)
# The library name is configurable since we are maintaining libraries of both
# debug/release mode.

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@ -3602,6 +3602,7 @@ std::vector<Status> DBImpl::MultiGet(
} else if (super_version->imm->Get(lkey, value, &s, &merge_context)) {
// Done
} else {
PERF_TIMER_GUARD(get_from_output_files_time);
super_version->current->Get(options, lkey, value, &s, &merge_context);
}

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@ -8,6 +8,7 @@
#include "db/db_impl.h"
#include "db/merge_context.h"
#include "db/db_iter.h"
#include "util/perf_context_imp.h"
namespace rocksdb {
@ -34,6 +35,7 @@ Status DBImplReadOnly::Get(const ReadOptions& read_options,
LookupKey lkey(key, snapshot);
if (super_version->mem->Get(lkey, value, &s, &merge_context)) {
} else {
PERF_TIMER_GUARD(get_from_output_files_time);
super_version->current->Get(read_options, lkey, value, &s, &merge_context);
}
return s;

View File

@ -6,7 +6,6 @@
#include <algorithm>
#include <iostream>
#include <vector>
#include "/usr/include/valgrind/callgrind.h"
#include "rocksdb/db.h"
#include "rocksdb/perf_context.h"
@ -29,7 +28,7 @@ const std::string kDbName = rocksdb::test::TmpDir() + "/perf_context_test";
namespace rocksdb {
std::shared_ptr<DB> OpenDb() {
std::shared_ptr<DB> OpenDb(bool read_only = false) {
DB* db;
Options options;
options.create_if_missing = true;
@ -39,12 +38,16 @@ std::shared_ptr<DB> OpenDb() {
FLAGS_min_write_buffer_number_to_merge;
if (FLAGS_use_set_based_memetable) {
auto prefix_extractor = rocksdb::NewFixedPrefixTransform(0);
options.memtable_factory.reset(
NewHashSkipListRepFactory(prefix_extractor));
options.prefix_extractor.reset(rocksdb::NewFixedPrefixTransform(0));
options.memtable_factory.reset(NewHashSkipListRepFactory());
}
Status s = DB::Open(options, kDbName, &db);
Status s;
if (!read_only) {
s = DB::Open(options, kDbName, &db);
} else {
s = DB::OpenForReadOnly(options, kDbName, &db);
}
ASSERT_OK(s);
return std::shared_ptr<DB>(db);
}
@ -76,7 +79,8 @@ TEST(PerfContextTest, SeekIntoDeletion) {
std::string value;
perf_context.Reset();
StopWatchNano timer(Env::Default(), true);
StopWatchNano timer(Env::Default());
timer.Start();
auto status = db->Get(read_options, key, &value);
auto elapsed_nanos = timer.ElapsedNanos();
ASSERT_TRUE(status.IsNotFound());
@ -149,11 +153,12 @@ TEST(PerfContextTest, StopWatchNanoOverhead) {
TEST(PerfContextTest, StopWatchOverhead) {
// profile the timer cost by itself!
const int kTotalIterations = 1000000;
uint64_t elapsed = 0;
std::vector<uint64_t> timings(kTotalIterations);
StopWatch timer(Env::Default());
StopWatch timer(Env::Default(), nullptr, 0, &elapsed);
for (auto& timing : timings) {
timing = timer.ElapsedMicros();
timing = elapsed;
}
HistogramImpl histogram;
@ -166,7 +171,7 @@ TEST(PerfContextTest, StopWatchOverhead) {
std::cout << histogram.ToString();
}
void ProfileKeyComparison() {
void ProfileQueries(bool enabled_time = false) {
DestroyDB(kDbName, Options()); // Start this test with a fresh DB
auto db = OpenDb();
@ -175,11 +180,21 @@ void ProfileKeyComparison() {
ReadOptions read_options;
HistogramImpl hist_put;
HistogramImpl hist_get;
HistogramImpl hist_get_snapshot;
HistogramImpl hist_get_memtable;
HistogramImpl hist_get_files;
HistogramImpl hist_get_post_process;
HistogramImpl hist_num_memtable_checked;
HistogramImpl hist_mget;
HistogramImpl hist_mget_snapshot;
HistogramImpl hist_mget_memtable;
HistogramImpl hist_mget_files;
HistogramImpl hist_mget_post_process;
HistogramImpl hist_mget_num_memtable_checked;
HistogramImpl hist_write_pre_post;
HistogramImpl hist_write_wal_time;
HistogramImpl hist_write_memtable_time;
@ -187,8 +202,13 @@ void ProfileKeyComparison() {
std::cout << "Inserting " << FLAGS_total_keys << " key/value pairs\n...\n";
std::vector<int> keys;
const int kFlushFlag = -1;
for (int i = 0; i < FLAGS_total_keys; ++i) {
keys.push_back(i);
if (i == FLAGS_total_keys / 2) {
// Issuing a flush in the middle.
keys.push_back(kFlushFlag);
}
}
if (FLAGS_random_key) {
@ -196,27 +216,54 @@ void ProfileKeyComparison() {
}
for (const int i : keys) {
if (i == kFlushFlag) {
FlushOptions fo;
db->Flush(fo);
continue;
}
std::string key = "k" + std::to_string(i);
std::string value = "v" + std::to_string(i);
std::vector<Slice> keys = {Slice(key)};
std::vector<std::string> values;
perf_context.Reset();
db->Put(write_options, key, value);
hist_write_pre_post.Add(perf_context.write_pre_and_post_process_time);
hist_write_wal_time.Add(perf_context.write_wal_time);
hist_write_memtable_time.Add(perf_context.write_memtable_time);
hist_put.Add(perf_context.user_key_comparison_count);
}
for (const int i : keys) {
std::string key = "k" + std::to_string(i);
std::string value = "v" + std::to_string(i);
std::vector<Slice> keys = {Slice(key)};
std::vector<std::string> values;
perf_context.Reset();
db->Get(read_options, key, &value);
hist_get_snapshot.Add(perf_context.get_snapshot_time);
hist_get_memtable.Add(perf_context.get_from_memtable_time);
hist_get_files.Add(perf_context.get_from_output_files_time);
hist_num_memtable_checked.Add(perf_context.get_from_memtable_count);
hist_get_post_process.Add(perf_context.get_post_process_time);
hist_get.Add(perf_context.user_key_comparison_count);
perf_context.Reset();
db->MultiGet(read_options, keys, &values);
hist_mget_snapshot.Add(perf_context.get_snapshot_time);
hist_mget_memtable.Add(perf_context.get_from_memtable_time);
hist_mget_files.Add(perf_context.get_from_output_files_time);
hist_mget_num_memtable_checked.Add(perf_context.get_from_memtable_count);
hist_mget_post_process.Add(perf_context.get_post_process_time);
hist_mget.Add(perf_context.user_key_comparison_count);
}
std::cout << "Put uesr key comparison: \n" << hist_put.ToString()
<< "Get uesr key comparison: \n" << hist_get.ToString();
<< "Get uesr key comparison: \n" << hist_get.ToString()
<< "MultiGet uesr key comparison: \n" << hist_get.ToString();
std::cout << "Put(): Pre and Post Process Time: \n"
<< hist_write_pre_post.ToString()
<< " Writing WAL time: \n"
@ -224,25 +271,139 @@ void ProfileKeyComparison() {
<< " Writing Mem Table time: \n"
<< hist_write_memtable_time.ToString() << "\n";
std::cout << "Get(): Time to get snapshot: \n"
std::cout << "Get(): Time to get snapshot: \n" << hist_get_snapshot.ToString()
<< " Time to get value from memtables: \n"
<< hist_get_memtable.ToString() << "\n"
<< " Time to get value from output files: \n"
<< hist_get_files.ToString() << "\n"
<< " Number of memtables checked: \n"
<< hist_num_memtable_checked.ToString() << "\n"
<< " Time to post process: \n" << hist_get_post_process.ToString()
<< "\n";
std::cout << "MultiGet(): Time to get snapshot: \n"
<< hist_mget_snapshot.ToString()
<< " Time to get value from memtables: \n"
<< hist_mget_memtable.ToString() << "\n"
<< " Time to get value from output files: \n"
<< hist_mget_files.ToString() << "\n"
<< " Number of memtables checked: \n"
<< hist_mget_num_memtable_checked.ToString() << "\n"
<< " Time to post process: \n" << hist_mget_post_process.ToString()
<< "\n";
if (enabled_time) {
ASSERT_GT(hist_get.Average(), 0);
ASSERT_GT(hist_get_snapshot.Average(), 0);
ASSERT_GT(hist_get_memtable.Average(), 0);
ASSERT_GT(hist_get_files.Average(), 0);
ASSERT_GT(hist_get_post_process.Average(), 0);
ASSERT_GT(hist_num_memtable_checked.Average(), 0);
ASSERT_GT(hist_mget.Average(), 0);
ASSERT_GT(hist_mget_snapshot.Average(), 0);
ASSERT_GT(hist_mget_memtable.Average(), 0);
ASSERT_GT(hist_mget_files.Average(), 0);
ASSERT_GT(hist_mget_post_process.Average(), 0);
ASSERT_GT(hist_mget_num_memtable_checked.Average(), 0);
}
db.reset();
db = OpenDb(true);
hist_get.Clear();
hist_get_snapshot.Clear();
hist_get_memtable.Clear();
hist_get_files.Clear();
hist_get_post_process.Clear();
hist_num_memtable_checked.Clear();
hist_mget.Clear();
hist_mget_snapshot.Clear();
hist_mget_memtable.Clear();
hist_mget_files.Clear();
hist_mget_post_process.Clear();
hist_mget_num_memtable_checked.Clear();
for (const int i : keys) {
std::string key = "k" + std::to_string(i);
std::string value = "v" + std::to_string(i);
std::vector<Slice> keys = {Slice(key)};
std::vector<std::string> values;
perf_context.Reset();
db->Get(read_options, key, &value);
hist_get_snapshot.Add(perf_context.get_snapshot_time);
hist_get_memtable.Add(perf_context.get_from_memtable_time);
hist_get_files.Add(perf_context.get_from_output_files_time);
hist_num_memtable_checked.Add(perf_context.get_from_memtable_count);
hist_get_post_process.Add(perf_context.get_post_process_time);
hist_get.Add(perf_context.user_key_comparison_count);
perf_context.Reset();
db->MultiGet(read_options, keys, &values);
hist_mget_snapshot.Add(perf_context.get_snapshot_time);
hist_mget_memtable.Add(perf_context.get_from_memtable_time);
hist_mget_files.Add(perf_context.get_from_output_files_time);
hist_mget_num_memtable_checked.Add(perf_context.get_from_memtable_count);
hist_mget_post_process.Add(perf_context.get_post_process_time);
hist_mget.Add(perf_context.user_key_comparison_count);
}
std::cout << "ReadOnly Get uesr key comparison: \n" << hist_get.ToString()
<< "ReadOnly MultiGet uesr key comparison: \n"
<< hist_mget.ToString();
std::cout << "ReadOnly Get(): Time to get snapshot: \n"
<< hist_get_snapshot.ToString()
<< " Time to get value from memtables: \n"
<< hist_get_memtable.ToString() << "\n"
<< " Time to get value from output files: \n"
<< hist_get_files.ToString() << "\n"
<< " Number of memtables checked: \n"
<< hist_num_memtable_checked.ToString() << "\n"
<< " Time to post process: \n"
<< hist_get_post_process.ToString() << "\n";
<< " Time to post process: \n" << hist_get_post_process.ToString()
<< "\n";
std::cout << "ReadOnly MultiGet(): Time to get snapshot: \n"
<< hist_mget_snapshot.ToString()
<< " Time to get value from memtables: \n"
<< hist_mget_memtable.ToString() << "\n"
<< " Time to get value from output files: \n"
<< hist_mget_files.ToString() << "\n"
<< " Number of memtables checked: \n"
<< hist_mget_num_memtable_checked.ToString() << "\n"
<< " Time to post process: \n" << hist_mget_post_process.ToString()
<< "\n";
if (enabled_time) {
ASSERT_GT(hist_get.Average(), 0);
ASSERT_GT(hist_get_memtable.Average(), 0);
ASSERT_GT(hist_get_files.Average(), 0);
ASSERT_GT(hist_num_memtable_checked.Average(), 0);
// In read-only mode Get(), no super version operation is needed
ASSERT_EQ(hist_get_post_process.Average(), 0);
ASSERT_EQ(hist_get_snapshot.Average(), 0);
ASSERT_GT(hist_mget.Average(), 0);
ASSERT_GT(hist_mget_snapshot.Average(), 0);
ASSERT_GT(hist_mget_memtable.Average(), 0);
ASSERT_GT(hist_mget_files.Average(), 0);
ASSERT_GT(hist_mget_post_process.Average(), 0);
ASSERT_GT(hist_mget_num_memtable_checked.Average(), 0);
}
}
TEST(PerfContextTest, KeyComparisonCount) {
SetPerfLevel(kEnableCount);
ProfileKeyComparison();
ProfileQueries();
SetPerfLevel(kDisable);
ProfileKeyComparison();
ProfileQueries();
SetPerfLevel(kEnableTime);
ProfileKeyComparison();
ProfileQueries(true);
}
// make perf_context_test