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Hi all,
I recently got many occurrences of this error on one of my AWS ColdFusion servers:
"Error","ajp-bio-8014-exec-138","02/19/16","08:45:25",,"GC overhead limit exceeded The specific sequence of files included or processed is: xxxxxxxxx.cfm'' "
where xxxxxxxxx.cfm are different files. I noticed this when CPU usage was high and expecially when my sites where damnly slow. Now I restarted ColdFusion Server but I would like to know what was the problem and how to resolve it.
My actual configuration is:
Ubuntu Server 64-bit 2vCPU 8 GB RAM with ColdFusion 11 update 7
Minimum JVM Heap Size: 4096 MB
Maximum JVM Heap Size: 4096 MB
-server -XX:MetaspaceSize=312m -XX:MaxMetaspaceSize=512m -XX:ReservedCodeCacheSize=240m -XX:CompressedClassSpaceSize=1g -XX:+UseParallelGC -Xbatch -Dcoldfusion.home={application.home} -Djava.security.egd=/dev/urandom -Duser.language=en -Dcoldfusion.rootDir={application.home} -Dcoldfusion.libPath={application.home}/lib -Dorg.apache.coyote.USE_CUSTOM_STATUS_MSG_IN_HEADER=true -Dcoldfusion.jsafe.defaultalgo=FIPS186Random -Dorg.eclipse.jetty.util.log.class=org.eclipse.jetty.util.log.JavaUtilLog
Thanks a lot for your help.
Here are a couple references. There are many other good sources of CF Java monitoring, you can do well to do some searching.
"Traditional" Java logging to a file then read file with gcviewer:
http://www.adobe.com/devnet/coldfusion/articles/coldfusion_performance.html
Using JDK tool JMC with CF having JMX (java management extensions) enabled:
http://www.cfwhisperer.com/post.cfm/using-java-mission-control-and-flight-recorder
HTH again, Carl M.
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What version of Java (JVM/JVK) are you using?
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Hi Carl, Coldfusion 11 update 7 should use Java 8.
Thanks
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xfreeman89x‌, I'm asking this so that the JVM experts can jump in here with the information they need. Specifically which JVM version are you actually using? Please check the System Information page in CF Administrator and let us know what is in the Java Version row under the JVM Details section. It should be something like 1.8.0_XX (where XX is the update level).
Thanks,
-Carl V.
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Hi,
I think some Java monitoring either by 1) doing traditional output to a log file and read the file or pass file thru a graphic tool like gcviewer or 2) install JDK enable JMX then use jconsole or jmc to see what the heap and non heap are doing.
I think you can do some searches and find references on how to do either of those plus I am going out so am in a hurry.
It sounds like FullGC are ocurring frequently but memory is not clearing. There is a JVM argument you can apply to silence the warning however not having the warning is no fix for the problem.
While those are the default values for ReservedCodeCacheSize and CompressedClassSpaceSize I tend to find CodeCache is not enough and CompressClass is to much. JDK tools like JMC will help to know.
HTH, Carl M.
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Here are a couple references. There are many other good sources of CF Java monitoring, you can do well to do some searching.
"Traditional" Java logging to a file then read file with gcviewer:
http://www.adobe.com/devnet/coldfusion/articles/coldfusion_performance.html
Using JDK tool JMC with CF having JMX (java management extensions) enabled:
http://www.cfwhisperer.com/post.cfm/using-java-mission-control-and-flight-recorder
HTH again, Carl M.