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Document the magic JVM flag to reduce CPU contention etc

Open tallpsmith opened this issue 10 years ago • 1 comments

This issue stems from the discovery many moons ago that for older Java+Linux Kernal combinations some of the Thread CPU metric collections were INSANELY SLOW.

To work around this, an evilly hidden JVM option was discovered: -XX:+UseLinuxPosixThreadCPUClocks

Which when active, drastically improved performance.

tallpsmith avatar Jan 30 '15 20:01 tallpsmith

Since the option is enabled by default on OpenJDK 1.7+ perhaps this issue can be closed?

myllynen avatar Feb 08 '18 07:02 myllynen

The flag has been on by default since java 7 and is now deprecated for removal.

https://bugs.openjdk.org/browse/JDK-8338947

pwinckles avatar Sep 06 '24 13:09 pwinckles