OOM on Windows 2008, WLS 10.3

Question

Customer running WLS 10.3 over JRockit - increasing heap size to 4G on 64bit system causes OOM exception!
1) He's using weblogic10.3 (10g) (64 bit) on Windows 2008 64bit version on Xeon processor with x86-x64 version jrockit1.6.0_05(jre)
2) When he uses Windows 2008 (64bit), Weblogic server 10.3 (64 bit), Sun JRE1.6.0_11 (64 bit) with heap size 4GB he is able to run WLS as a windows service.
3) Also, when he uses Windows 2008 (64bit), Weblogic server 10.3 (64 Bit), jrockit1.6.0_05 (jre) (64 bit) with heap size 2GB he is able to run WLS as a windows service.
4) FAILURE: when he uses Windows 2008 (64bit), Weblogic server 10.3 (64 Bit), jrockit1.6.0_05 (jre) (64 bit) with heap size 4GB, WLS gets installed as windows service but the service is not getting started and it exit immediately.
2) Environment:
-WLS : 10g (10.3) (64 bit)
-Database : MS SQL server
-JVM : JRockit 1.6.0_05 (64 bit)
-OS : Windows 2008 (64bit). 4G physical RAM.
What gives? Increasing the heap size causes an OOM. This would imply (if I read the docs correctly) that JRockit can't get enough virtual memory. But I believe (still waiting to confirm) that the Windows OS has a "standard" virtual memory setting, which would imply much more virtual memory than the 4G physical RAM. So this is a mystery. Any pointers/clues?
Toby

Answer 1

Try to start JRockit with -XXcompressedRefs=false or set the heap size to slightly above 4 GB.
Regards,
Henrik