Merge pull request #17416 from ClickHouse/tavplubix-patch-2

Fix backoff in BackgroundJobExecutor
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alesapin 2020-11-26 16:43:15 +03:00 committed by GitHub
commit 6719fb3a1d
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2 changed files with 29 additions and 30 deletions

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@ -36,16 +36,14 @@ double IBackgroundJobExecutor::getSleepRandomAdd()
return std::uniform_real_distribution<double>(0, sleep_settings.task_sleep_seconds_when_no_work_random_part)(rng);
}
void IBackgroundJobExecutor::scheduleTask(bool job_done, bool with_backoff)
{
if (job_done)
void IBackgroundJobExecutor::runTaskWithoutDelay()
{
no_work_done_count = 0;
/// We have background jobs, schedule task as soon as possible
scheduling_task->schedule();
}
else
void IBackgroundJobExecutor::scheduleTask(bool with_backoff)
{
size_t next_time_to_execute;
if (with_backoff)
@ -64,7 +62,6 @@ void IBackgroundJobExecutor::scheduleTask(bool job_done, bool with_backoff)
scheduling_task->scheduleAfter(next_time_to_execute, false);
}
}
namespace
{
@ -105,42 +102,42 @@ try
/// Job done, decrement metric and reset no_work counter
CurrentMetrics::values[pool_config.tasks_metric]--;
/// Job done, new empty space in pool, schedule background task
scheduleTask(true);
runTaskWithoutDelay();
}
catch (...)
{
tryLogCurrentException(__PRETTY_FUNCTION__);
CurrentMetrics::values[pool_config.tasks_metric]--;
scheduleTask(false);
scheduleTask(/* with_backoff = */ true);
}
});
/// We've scheduled task in the background pool and when it will finish we will be triggered again. But this task can be
/// extremely long and we may have a lot of other small tasks to do, so we schedule ourselves here.
scheduleTask(true);
runTaskWithoutDelay();
}
catch (...)
{
/// With our Pool settings scheduleOrThrowOnError shouldn't throw exceptions, but for safety catch added here
tryLogCurrentException(__PRETTY_FUNCTION__);
CurrentMetrics::values[pool_config.tasks_metric]--;
scheduleTask(false);
scheduleTask(/* with_backoff = */ true);
}
}
else /// Pool is full and we have some work to do
{
scheduleTask(false, /* with_backoff = */ false);
scheduleTask(/* with_backoff = */ false);
}
}
else /// Nothing to do, no jobs
{
scheduleTask(false);
scheduleTask(/* with_backoff = */ true);
}
}
catch (...) /// Exception while we looking for a task, reschedule
{
tryLogCurrentException(__PRETTY_FUNCTION__);
scheduleTask(false);
scheduleTask(/* with_backoff = */ true);
}
void IBackgroundJobExecutor::start()

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@ -117,7 +117,9 @@ private:
/// Function that executes in background scheduling pool
void jobExecutingTask();
/// Recalculate timeouts when we have to check for a new job
void scheduleTask(bool job_done, bool with_backoff=false);
void scheduleTask(bool with_backoff);
/// Run background task as fast as possible and reset errors counter
void runTaskWithoutDelay();
/// Return random add for sleep in case of error
double getSleepRandomAdd();
};