-XX:SurvivorRatio JVM option

Hi everyone!

I launched my application using for GARBAGE COLLECTION these options:

-Xmx512m -Xms512m -XX:MaxNewSize=24m -XX:NewSize=24m -XX:SurvivorRatio=2 -XX:+UseConcMarkSweepGC -XX:+UseParNewGC

SurvivorRatio is 2, so I expect two survivors spaces of 6 MB each one and an eden space of 12 MB. GC log files (PrintGC options used) surprised me: Eden space is almost all NewSize and two Survivors spaces are only 64KB each one.

If I don't use -XX:+UseConcMarkSweepGC -XX:+UseParNewGC options, spaces have the values expected (12 MB Eden, 6 MB each one survivors space).

Why does JVM behave in this way?

Thank you very much in advance.

Diego

[706 byte] By [DiegoCarzanigaa] at [2007-10-3 11:09:09]
# 1

This is a bug in older versions of the JVM fixed more

recently. I do not have the bug id handy, but a workaround

is to additionally also specify a -XX:MaxTenuringThreshold=<n>,

where n is in [1,..,15] for example -XX:MaxTenuringThreshold=12.

Try 1.5.0_09 or 1.6, perhaps even 1.4.2_12, where this bug should

have been fixed, IIRC.

ramki_at_jdca at 2007-7-15 13:32:11 > top of Java-index,Java HotSpot Virtual Machine,Specifications...
# 2
Thank you very much for your help!Bye!Diego
DiegoCarzanigaa at 2007-7-15 13:32:11 > top of Java-index,Java HotSpot Virtual Machine,Specifications...