andreacavalli/rocksdb
0
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

Still use SystemClock* instead of shared_ptr in StepPerfTimer (#8006)

Browse Source 
Summary:
This is likely a temp fix before we figure out a better way.

PerfStepTimer is used intensively in certain benchmarking/testings. https://github.com/facebook/rocksdb/issues/7858 stores a `shared_ptr` to system clock in PerfStepTimer which gets created each time a `PerfStepTimer` object is created. The atomic operations in `shared_ptr` may add overhead in CPU cycles. Therefore, we change it back to a raw `SystemClock*` for now.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8006

Test Plan: make check

Reviewed By: pdillinger

Differential Revision: D26703560

Pulled By: riversand963

fbshipit-source-id: 519d0769b28da2334bea7d86c848fcc26ee8a17f
This commit is contained in:
Yanqin Jin 2021-02-26 20:55:54 -08:00 committed by Facebook GitHub Bot
parent a8b3b9a20c
commit 9fdc9fbeea
3 changed files with 7 additions and 8 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
monitoring/iostats_context_imp.h
View File

@ -40,7 +40,7 @@ extern __thread IOStatsContext iostats_context;
// Declare and set start time of the timer
#define IOSTATS_CPU_TIMER_GUARD(metric, clock) \
PerfStepTimer iostats_step_timer_##metric( \
&(iostats_context.metric), clock, true, \
&(iostats_context.metric), clock.get(), true, \
PerfLevel::kEnableTimeAndCPUTimeExceptForMutex); \
iostats_step_timer_##metric.Start();

4
monitoring/perf_context_imp.h
View File

@ -47,13 +47,13 @@ extern thread_local PerfContext perf_context;
// Declare and set start time of the timer
#define PERF_TIMER_GUARD_WITH_CLOCK(metric, clock) \
PerfStepTimer perf_step_timer_##metric(&(perf_context.metric), clock); \
PerfStepTimer perf_step_timer_##metric(&(perf_context.metric), clock.get()); \
perf_step_timer_##metric.Start();
// Declare and set start time of the timer
#define PERF_CPU_TIMER_GUARD(metric, clock) \
PerfStepTimer perf_step_timer_##metric( \
&(perf_context.metric), clock, true, \
&(perf_context.metric), clock.get(), true, \
PerfLevel::kEnableTimeAndCPUTimeExceptForMutex); \
perf_step_timer_##metric.Start();

7
monitoring/perf_step_timer.h
View File

@ -13,14 +13,13 @@ namespace ROCKSDB_NAMESPACE {
class PerfStepTimer {
public:
explicit PerfStepTimer(
uint64_t* metric, const std::shared_ptr<SystemClock>& clock = nullptr,
bool use_cpu_time = false,
uint64_t* metric, SystemClock* clock = nullptr, bool use_cpu_time = false,
PerfLevel enable_level = PerfLevel::kEnableTimeExceptForMutex,
Statistics* statistics = nullptr, uint32_t ticker_type = 0)
: perf_counter_enabled_(perf_level >= enable_level),
use_cpu_time_(use_cpu_time),
clock_((perf_counter_enabled_ || statistics != nullptr)
? ((clock.get() != nullptr) ? clock : SystemClock::Default())
? (clock ? clock : SystemClock::Default().get())
: nullptr),
start_(0),
metric_(metric),
@ -70,7 +69,7 @@ class PerfStepTimer {
const bool perf_counter_enabled_;
const bool use_cpu_time_;
std::shared_ptr<SystemClock> clock_;
SystemClock* const clock_;
uint64_t start_;
uint64_t* metric_;
Statistics* statistics_;