rocksdb/util/instrumented_mutex.cc
sdong d20915d52a Disable stats about mutex duration by default
Summary: Measuring mutex duration will measure time inside DB mutex, which breaks our best practice. Add a stat level in Statistics class. By default, disable to measure the mutex operations.

Test Plan: Add a unit test to make sure it is off by default.

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

Reviewed By: yhchiang

Subscribers: MarkCallaghan, leveldb, dhruba

Differential Revision: https://reviews.facebook.net/D53367
2016-01-26 14:56:55 -08:00

87 lines
2.5 KiB
C++

// Copyright (c) 2015, 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 "util/instrumented_mutex.h"
#include "util/perf_context_imp.h"
#include "util/thread_status_util.h"
namespace rocksdb {
namespace {
bool ShouldReportToStats(Env* env, Statistics* stats) {
return env != nullptr && stats != nullptr &&
stats->stats_level_ != kExceptTimeForMutex;
}
} // namespace
void InstrumentedMutex::Lock() {
PERF_CONDITIONAL_TIMER_FOR_MUTEX_GUARD(db_mutex_lock_nanos,
stats_code_ == DB_MUTEX_WAIT_MICROS);
uint64_t wait_time_micros = 0;
if (ShouldReportToStats(env_, stats_)) {
{
StopWatch sw(env_, nullptr, 0, &wait_time_micros);
LockInternal();
}
RecordTick(stats_, stats_code_, wait_time_micros);
} else {
LockInternal();
}
}
void InstrumentedMutex::LockInternal() {
#ifndef NDEBUG
ThreadStatusUtil::TEST_StateDelay(ThreadStatus::STATE_MUTEX_WAIT);
#endif
mutex_.Lock();
}
void InstrumentedCondVar::Wait() {
PERF_CONDITIONAL_TIMER_FOR_MUTEX_GUARD(db_condition_wait_nanos,
stats_code_ == DB_MUTEX_WAIT_MICROS);
uint64_t wait_time_micros = 0;
if (ShouldReportToStats(env_, stats_)) {
{
StopWatch sw(env_, nullptr, 0, &wait_time_micros);
WaitInternal();
}
RecordTick(stats_, stats_code_, wait_time_micros);
} else {
WaitInternal();
}
}
void InstrumentedCondVar::WaitInternal() {
#ifndef NDEBUG
ThreadStatusUtil::TEST_StateDelay(ThreadStatus::STATE_MUTEX_WAIT);
#endif
cond_.Wait();
}
bool InstrumentedCondVar::TimedWait(uint64_t abs_time_us) {
PERF_CONDITIONAL_TIMER_FOR_MUTEX_GUARD(db_condition_wait_nanos,
stats_code_ == DB_MUTEX_WAIT_MICROS);
uint64_t wait_time_micros = 0;
bool result = false;
if (ShouldReportToStats(env_, stats_)) {
{
StopWatch sw(env_, nullptr, 0, &wait_time_micros);
result = TimedWaitInternal(abs_time_us);
}
RecordTick(stats_, stats_code_, wait_time_micros);
} else {
result = TimedWaitInternal(abs_time_us);
}
return result;
}
bool InstrumentedCondVar::TimedWaitInternal(uint64_t abs_time_us) {
#ifndef NDEBUG
ThreadStatusUtil::TEST_StateDelay(ThreadStatus::STATE_MUTEX_WAIT);
#endif
return cond_.TimedWait(abs_time_us);
}
} // namespace rocksdb