CMS collection keep working during holiday

Y Srinivas Ramakrishna Y.S.Ramakrishna at Sun.COM
Wed Oct 8 05:26:34 UTC 2008

Could you run with the additional option +PrintReferenceGC and see if
it sheds additional light on the problem? (Please share the resulting
GC logs.)

If at all possible, you might try rev'ing down to 6.0 and seeing
if the same behaviour reproduces or not?

I understand that some or all of this may not be possible in a
production setting.

-- ramki

----- Original Message -----
From: "Ken-- at" <dragonken at>
Date: Tuesday, October 7, 2008 10:17 pm
Subject: Re: CMS collection keep working during holiday
To: hotspot-gc-dev at

> Follow up to the jconsole above. This gif is captured today. You can 
> see the
> first CMS after a FULL GC is working. The 2nd one is working too but the
> memory free from 2nd generation is much less than the first CMS. The memory
> free by 3rd CMS is further decreased.
> The 5th CMS cannot free enough memory to make occanpcy in old-gen to less
> than 70%. So, continue non-stopping CMS happen again until a Full GC
> (triggered by Concurrent Mode Failure).
> -- 
> View this message in context:
> Sent from the OpenJDK Hotspot Garbage Collection mailing list archive 
> at

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