Service Virtualization

Hello All,

I've have updated DevTest (from 8.1/embedded jdk 1.7) to version 10.1 (embedded jdk 1.8).

For performance testing on DevTest 8.1, we were using following GC parameters : 

-XX:+UseConcMarkSweepGC

-XX:+CMSIncrementalMode

-XX:+CMSIncrementalPacing

-XX:MaxGCPauseMillis=500

On DevTest 10.1, can I use the same or are there any other recommendations ?

Thanks, 

Benoit

JDK 1.8 implements a different set of heap allocation and management strategies.

Generally speaking, the GC strategy has been taken care of by the product engineering team during hardening of the release.

I would not recommend overriding the GC strategy of any DevTest release executing on JDK 1.8 or higher unless directed to do so by CA Support.

ok, thanks.

Hi Benoit,

In general support recommends using the default garbage collector except in two specific instances.

1. Performance VSE (or other overloaded DevTest components):
We recommend using the Mark Sweep garbage collect, with the exact same settings you listed.
-XX:+UseConcMarkSweepGC
-XX:+CMSIncrementalMode
-XX:+CMSIncrementalPacing
-XX:MaxGCPauseMillis=500

This GC minimizes "stop the world" garbage collections resulting in a paused applications (all java programs, not just DevTest).

2. If the JVM's heap size is over 4GB (this is rare), we recommend using the "Garbage First" Collector:
Replace the top line above with: –XX:+UseG1GC
This GC also minimizes "stop the world" type collections but does not suffer from memory fragmentation like the Mark Sweep collector can with a large JVM. As stated, this collector is recommended for JVM's over 4GB.

I hope this helps.

Best Regards,
Ricky
CA DevTest Support

Thanks, it helps.

Best regards,

Benoit