What do -XX:-PrintGC and XX:-PrintGCDetails flags do?

java garbage-collection jvm jvm-hotspot
ripper234 picture ripper234 · Nov 29, 2009 · Viewed 47.7k times · Source

I found the JVM flags here. Is there a more detailed explaination of what exactly they do?

Answer

Jé Queue picture Jé Queue · Nov 30, 2009

Rather on Sun's, use -Xloggc:gc.log to log to a file, -verbose:gc is also a common switch for this.

Also, ensure -XX:+PrintGCDetails and -XX:+PrintGCTimeStamps (note the plus + sign). The timestamp switch is redundant but good to include.

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