Apache Tomcat 7 Configuration Reference (7.0.70) - The Executor (thread pool)
Author: Filip Hanik

| # Apache Tomcat 7 Version 7.0.70, Jun 15 2016 |

Links Docs Home Config Ref. Home FAQ User Comments Top Level Elements Server Service Executors Executor Connectors HTTP AJP Containers Context Engine Host Cluster Nested Components Global Resources JarScanner Listeners Loader Manager Realm Resources SessionIdGenerator Valve Cluster Elements Cluster Manager Channel Channel/Membership Channel/Sender Channel/Receiver Channel/Interceptor Valve Deployer ClusterListener web.xml Filter Other System properties | # The Executor (thread pool)
Table of Contents
Introduction Attributes Common Attributes Standard Implementation
Introduction
The Executor represents a thread pool that can be shared between components in Tomcat. Historically there has been a thread pool per connector created but this allows you to share a thread pool, between (primarily) connector but also other components when those get configured to support executors The executor has to implement the `org.apache.catalina.Executor` interface. The executor is a nested element to the Service element. And in order for it to be picked up by the connectors, the Executor element has to appear prior to the Connector element in server.xml
Attributes
> Common Attributes
> > All implementations of Executor support the following attributes:
> > Attribute | Description
> > --- | ---
> > `className` | The class of the implementation. The implementation has to implement the `org.apache.catalina.Executor` interface. This interface ensures that the object can be referenced through its `name` attribute and that implements Lifecycle, so that it can be started and stopped with the container. The default value for the className is `org.apache.catalina.core.StandardThreadExecutor`
> > `name` | The name used to reference this pool in other places in server.xml. The name is required and must be unique.
> Standard Implementation
> > The default implementation supports the following attributes:
> > Attribute | Description
> > --- | ---
> > `threadPriority` | (int) The thread priority for threads in the executor, the default is `5` (the value of the `Thread.NORM_PRIORITY` constant)
> > `daemon` | (boolean) Whether the threads should be daemon threads or not, the default is `true`
> > `namePrefix` | (String) The name prefix for each thread created by the executor. The thread name for an individual thread will be `namePrefix+threadNumber`
> > `maxThreads` | (int) The max number of active threads in this pool, default is `200`
> > `minSpareThreads` | (int) The minimum number of threads always kept alive, default is `25`
> > `maxIdleTime` | (int) The number of milliseconds before an idle thread shutsdown, unless the number of active threads are less or equal to minSpareThreads. Default value is `60000`(1 minute)
> > `maxQueueSize` | (int) The maximum number of runnable tasks that can queue up awaiting execution before we reject them. Default value is `Integer.MAX_VALUE`
> > `prestartminSpareThreads` | (boolean) Whether minSpareThreads should be started when starting the Executor or not, the default is `false`
> > `threadRenewalDelay` | (long) If a ThreadLocalLeakPreventionListener is configured, it will notify this executor about stopped contexts. After a context is stopped, threads in the pool are renewed. To avoid renewing all threads at the same time, this option sets a delay between renewal of any 2 threads. The value is in ms, default value is `1000` ms. If value is negative, threads are not renewed.
Comments
Notice: This comments section collects your suggestions on improving documentation for Apache Tomcat. If you have trouble and need help, read Find Help page and ask your question on the tomcat-users mailing list. Do not ask such questions here. This is not a Q&A section. The Apache Comments System is explained here. Comments may be removed by our moderators if they are either implemented or considered invalid/off-topic.
Copyright © 1999-2016, Apache Software Foundation