Troublesome reflection-cached SoftReferences

Jon Masamitsu Jon.Masamitsu at Sun.COM
Fri Apr 24 18:50:25 UTC 2009

Charles Oliver Nutter wrote On 04/24/09 07:02,:

>Jon Masamitsu wrote:
>>Which garbage collector and which jdk release are you using?
>Java HotSpot(TM) 64-Bit Server VM version 1.6.0_07-b06-57
>Garbage collector: Name = 'Copy'
>Garbage collector: Name = 'MarkSweepCompact'
I'm don't know how Apple has set it's defaults and the names
above are not specific enough.

Can you run the command

java -XX:+PrintGCDetails -XX:+PrintCommandLineFlags -version

You should get output such as

java -XX:+PrintGCDetails -XX:+PrintCommandLineFlags -version
-XX:MaxHeapSize=1073741824 -XX:+PrintCommandLineFlags
-XX:+PrintGCDetails -XX:+UseParallelGC
java version "1.6.0"
Java(TM) SE Runtime Environment (build 1.6.0-b105)
Java HotSpot(TM) Server VM (build 1.6.0-b105, mixed mode)
 PSYoungGen      total 12544K, used 215K [0xf4000000, 0xf4e00000,
  eden space 10752K, 2% used [0xf4000000,0xf4035c38,0xf4a80000)
  from space 1792K, 0% used [0xf4c40000,0xf4c40000,0xf4e00000)
  to   space 1792K, 0% used [0xf4a80000,0xf4a80000,0xf4c40000)
 PSOldGen        total 110592K, used 0K [0xbb000000, 0xc1c00000, 0xf4000000)
  object space 110592K, 0% used [0xbb000000,0xbb000000,0xc1c00000)
 PSPermGen       total 16384K, used 1449K [0xb7000000, 0xb8000000,
  object space 16384K, 8% used [0xb7000000,0xb716a5b8,0xb8000000)

This will tell us exactly what is being run.

>These are the defaults running on Mac. Yes, this is the Apple JDK, but 
>we've reproduces these issues under Sun/OpenJDK as well. I'm really just 
>trying to figure out *why* all this stuff is sticking around, and the 
>soft reference has been my first solid lead.
>- Charlie
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