JDK6 YoungGen Layout

[Kobe Bryant]

i am using jdk1.6. I configureg Xmx = 2G, Xms= 2G, NewSize = MaxNewSize =
660m

I enable verbose gc. I see this which I am not understanding:


PSYoungGen      total 608256K, used 32440K
 eden space 540672K, 6% used
 from space 67584K, 0% used
 to   space 67584K, 0% used


According to my configuration YoungGen size is 675840MB. Because younGen =
Eden + two survivor spaces,
which matches my understanding what the YoungGen size should be.

GC log saying that my YoungGen size = 608256K which is not what i've
configured. Also if I add Eden space and two survivor spaces I am getting
540672K + 67584K + 67584K = 675840K

Eden + 1 Survivor space = 540672K + 67584K = 675840K, what i have
configured. So does this mean that YoungGen = Eden + 1 Survivor space? I
think there are two survivor space, correct?

Please explain me.

thanking you
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://mail.openjdk.java.net/pipermail/hotspot-gc-use/attachments/20120328/97f9e51b/attachment-0001.html