Package jenkins.metrics.util

Class HealthChecksThreadPool

java.lang.Object

java.util.concurrent.AbstractExecutorService

java.util.concurrent.ThreadPoolExecutor

jenkins.metrics.util.HealthChecksThreadPool

All Implemented Interfaces:

Executor, ExecutorService

public class HealthChecksThreadPool
extends ThreadPoolExecutor

Thread pool for running health checks. We set the pool size to 4 by default (configurable with system property jenkins.metrics.util.HealthChecksThreadPool.maxThreadNumber) and we keep threads around for 5 seconds as this is a bursty pool used once per minute. The queue size is limited to the current number of health checks dynamically, minus the 4 threads in the pool, plus one, as the Metrics.HealthChecker itself is executed in the pool too. For example for 10 health checks we have the thread pool (4) + the queue (7) = 11 for the 10 health checks and the HealthChecker. The RejectedExecutionHandler is configured to drop oldest items in the queue as new ones come in, to avoid running more than one health check in each recurrence period.

Since:

3.1.2.3

Nested Class Summary

Nested classes/interfaces inherited from class java.util.concurrent.ThreadPoolExecutor

ThreadPoolExecutor.AbortPolicy, ThreadPoolExecutor.CallerRunsPolicy, ThreadPoolExecutor.DiscardOldestPolicy, ThreadPoolExecutor.DiscardPolicy

Constructor Summary

Constructors

Constructor	Description
HealthChecksThreadPool(com.codahale.metrics.health.HealthCheckRegistry healthCheckRegistry)

Method Summary

Modifier and Type	Method	Description
protected void	beforeExecute(Thread t, Runnable r)	Manually handle the queue size so it doesn't grow over our calculated queue capacity based on the number of health checks
static long	getRejectedExecutions()

Methods inherited from class java.util.concurrent.ThreadPoolExecutor

afterExecute, allowCoreThreadTimeOut, allowsCoreThreadTimeOut, awaitTermination, execute, finalize, getActiveCount, getCompletedTaskCount, getCorePoolSize, getKeepAliveTime, getLargestPoolSize, getMaximumPoolSize, getPoolSize, getQueue, getRejectedExecutionHandler, getTaskCount, getThreadFactory, isShutdown, isTerminated, isTerminating, prestartAllCoreThreads, prestartCoreThread, purge, remove, setCorePoolSize, setKeepAliveTime, setMaximumPoolSize, setRejectedExecutionHandler, setThreadFactory, shutdown, shutdownNow, terminated, toString

Methods inherited from class java.util.concurrent.AbstractExecutorService

invokeAll, invokeAll, invokeAny, invokeAny, newTaskFor, newTaskFor, submit, submit, submit

Methods inherited from class java.lang.Object

clone, equals, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

HealthChecksThreadPool

public HealthChecksThreadPool(com.codahale.metrics.health.HealthCheckRegistry healthCheckRegistry)

Method Detail

beforeExecute

protected void beforeExecute(Thread t,
                             Runnable r)

Manually handle the queue size so it doesn't grow over our calculated queue capacity based on the number of health checks

Overrides:

beforeExecute in class ThreadPoolExecutor

getRejectedExecutions

@Restricted(org.kohsuke.accmod.restrictions.DoNotUse.class)
public static long getRejectedExecutions()