RFR: 8027423: Parallel compact GC class unloading measurement includes symbol and string table time

Mikael Gerdin mikael.gerdin at oracle.com
Mon Mar 14 15:39:58 UTC 2016

Hi Stefan,

On 2016-03-14 15:22, Stefan Karlsson wrote:
> Hi all,
> Please review this patch to get more detailed phase measurements of the
> unloading phases of the parallel and serial collectors. It mimics the
> way CMS reports the unloading phase. G1 parallelizes the unloading
> phase, so it is slightly different.
> http://cr.openjdk.java.net/~stefank/8027423/webrev.00/

Looks good.


> https://bugs.openjdk.java.net/browse/JDK-8027423
> Example of the output that you get with -Xlog:gc=debug:
> [2.257s][debug][gc] GC(45) Class Unloading (2.256s, 2.257s) 1.669ms
> [2.258s][debug][gc] GC(45) Scrub String Table (2.257s, 2.258s) 0.412ms
> [2.259s][debug][gc] GC(45) Scrub Symbol Table (2.258s, 2.259s) 1.027ms
> [2.292s][info ][gc] GC(45) Pause Full (System.gc()) 80M->2M(98M)
> (2.248s, 2.292s) 44.631ms
> Thanks,
> StefanK

More information about the hotspot-gc-dev mailing list