Allow Jetty's thread pool to be configured via the environment

[dmwb]

Hello,

I'm wondering, if it is possible to have some basic configuration for embedded Jetty in application.properties. Right now to customize thread pool and idle timeout, we're creating bean, which is not convenient...

    @Bean
    public JettyEmbeddedServletContainerFactory jettyEmbeddedServletContainerFactory() {
        final JettyEmbeddedServletContainerFactory factory = new JettyEmbeddedServletContainerFactory(serverProperties.getPort());
        factory.addServerCustomizers((Server server) -> {
            final QueuedThreadPool threadPool = server.getBean(QueuedThreadPool.class);
            threadPool.setMinThreads(appProperties.getMinThreads());
            threadPool.setMaxThreads(appProperties.getMaxThreads());
            threadPool.setIdleTimeout(appProperties.getIdleTimeout());
        });
        return factory;
    }

Could we have something similar like for tomcat and undertow. F.e.

server.jetty.max-threads
server.jetty.min-threads
server.jetty.idle-timeout

Or make it more generic. I'm pretty sure each servlet container has ability to configure such properties.

Thanks!

[wilkinsona]

See also #5324

[wilkinsona]

We already have the following properties:

server.tomcat.max-threads
server.undertow.io-threads
server.undertow.worker-threads

Tomcat's AbstractProtocol also supports configuring the minimum number of spare threads for which we do not have a property.

Jetty uses a QueueThreadPool by default. It has three simple properties:

maxThreads (default 200)
minThreads (default 8)
idleTimeout (default 60000)

It also allows its BlockQueue to be configured. It defaults to a BlockingArrayQueue which is unbounded with an initial capacity of the bigger of 8 and the minimum number of threads.

[dmwb]

Thanks in advance! Jetty is widely used and having these common parameters configured via application properties etc. will make Boot more efficient...

[btridip-in]

Is there a way to specify the max threads via the configuration (.yml) file to control how many concurrent requests can be serviced by the instance at any point in time?

[wilkinsona]

@btridip-in No, that's what this issue is about and it's still open. We have made it easier to configure it programmatically. See #5324 that was included in 1.4.