CMS collection keep working during holiday

kirk kirk.pepperdine at
Thu Oct 9 17:03:52 UTC 2008

Tony Printezis wrote:
> Y Srinivas Ramakrishna wrote:
>> If you use jmap -histo:live <pid> from the command-line you will
>> get a full gc before the histogram is computed. This full gc will
>> be done despite having +DisableExplicitGC.
> In fact, given that we want to find out what's growing in the heap 
> during the CMS cycles (which seems to be GCed during Full GCs), it's 
> better to use jmap -histo (i.e., no :live) to avoid the Full GC. But 
> I'm forgetting: which VM Ken using? IIRC only jmap in 6 has the :live 
> / no :live functionality (before that, it always did a Full GC, which 
> is not what you want some of the time).

What I found interesting was the diff between the live and full 
histogram as it seems to be an indicator of churn.

-- Kirk

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