High CPU load with the JSSE client poller on Tomcat 8.5

问题

I'm running a Tomcat 8.5.3 on Windows Server 2008R2 and Java 1.8.0_92. The process is consuming a lot of CPU (~ 50% from 4 CPUs).

JTop shows that the two most consuming threads are, by far, https-jsse-nio-443-ClientPoller-0 and https-jsse-nio-443-ClientPoller-1.

The threads are mainly looping on thes four stacktraces :

sun.nio.ch.WindowsSelectorImpl$SubSelector.poll0(Native Method)
sun.nio.ch.WindowsSelectorImpl$SubSelector.poll(WindowsSelectorImpl.java:296)
sun.nio.ch.WindowsSelectorImpl$SubSelector.access$400(WindowsSelectorImpl.java:278)
sun.nio.ch.WindowsSelectorImpl.doSelect(WindowsSelectorImpl.java:159)
sun.nio.ch.SelectorImpl.lockAndDoSelect(SelectorImpl.java:86)
   - locked sun.nio.ch.Util$2@2a3e6629
   - locked java.util.Collections$UnmodifiableSet@7cdb1cd3
   - locked sun.nio.ch.WindowsSelectorImpl@13dc3a00
sun.nio.ch.SelectorImpl.select(SelectorImpl.java:97)
org.apache.tomcat.util.net.NioEndpoint$Poller.run(NioEndpoint.java:791)
java.lang.Thread.run(Thread.java:745)

sun.nio.ch.WindowsSelectorImpl$SubSelector.processFDSet(WindowsSelectorImpl.java:345)
sun.nio.ch.WindowsSelectorImpl$SubSelector.processSelectedKeys(WindowsSelectorImpl.java:315)
sun.nio.ch.WindowsSelectorImpl$SubSelector.access$2900(WindowsSelectorImpl.java:278)
sun.nio.ch.WindowsSelectorImpl.updateSelectedKeys(WindowsSelectorImpl.java:495)
sun.nio.ch.WindowsSelectorImpl.doSelect(WindowsSelectorImpl.java:172)
sun.nio.ch.SelectorImpl.lockAndDoSelect(SelectorImpl.java:86)
   - locked sun.nio.ch.Util$2@6f4350d0
   - locked java.util.Collections$UnmodifiableSet@36157c3f
   - locked sun.nio.ch.WindowsSelectorImpl@120cc3aa
sun.nio.ch.SelectorImpl.select(SelectorImpl.java:97)
org.apache.tomcat.util.net.NioEndpoint$Poller.run(NioEndpoint.java:791)
    java.lang.Thread.run(Thread.java:745)

sun.nio.ch.WindowsSelectorImpl.resetWakeupSocket0(Native Method)
sun.nio.ch.WindowsSelectorImpl.resetWakeupSocket(WindowsSelectorImpl.java:473)
   - locked java.lang.Object@450e5040
sun.nio.ch.WindowsSelectorImpl.doSelect(WindowsSelectorImpl.java:174)
sun.nio.ch.SelectorImpl.lockAndDoSelect(SelectorImpl.java:86)
   - locked sun.nio.ch.Util$2@6f4350d0
   - locked java.util.Collections$UnmodifiableSet@36157c3f
   - locked sun.nio.ch.WindowsSelectorImpl@120cc3aa
sun.nio.ch.SelectorImpl.select(SelectorImpl.java:97)
org.apache.tomcat.util.net.NioEndpoint$Poller.run(NioEndpoint.java:791)
java.lang.Thread.run(Thread.java:745)

java.lang.Object.notifyAll(Native Method)
sun.nio.ch.WindowsSelectorImpl$StartLock.startThreads(WindowsSelectorImpl.java:189)
   - locked sun.nio.ch.WindowsSelectorImpl$StartLock@1c512d03
sun.nio.ch.WindowsSelectorImpl$StartLock.access$300(WindowsSelectorImpl.java:181)
sun.nio.ch.WindowsSelectorImpl.doSelect(WindowsSelectorImpl.java:153)
sun.nio.ch.SelectorImpl.lockAndDoSelect(SelectorImpl.java:86)
   - locked sun.nio.ch.Util$2@2a3e6629
   - locked java.util.Collections$UnmodifiableSet@7cdb1cd3
   - locked sun.nio.ch.WindowsSelectorImpl@13dc3a00
sun.nio.ch.SelectorImpl.select(SelectorImpl.java:97)
org.apache.tomcat.util.net.NioEndpoint$Poller.run(NioEndpoint.java:791)
java.lang.Thread.run(Thread.java:745)

Any idea ?

回答1:

I had a similar problem on Tomcat 8.5.4 / Linux where I saw very high cpu usage on the poller threads (eg, https-jsse-nio-443-ClientPoller-0 and 1). Upgrading to 8.5.5 seems to have resolved the issue.

May have been this bug: https://bz.apache.org/bugzilla/show_bug.cgi?id=60030

来源：https://stackoverflow.com/questions/38895884/high-cpu-load-with-the-jsse-client-poller-on-tomcat-8-5

标签

java

Tomcat

cpu-usage