jon.masamitsu at oracle.com
Thu Feb 9 06:39:22 PST 2012
I cannot say that I would recommend it's use. The problem with
is all in the policy that it uses to decide how to move the boundary.
It used to sometimes
back itself into a corner (young gen size and old gen size which was sub
and not be able to get itself out. I think that can still be a problem
but perhaps the
bigger problem is that the policy thinks that it is optimal to divide
the the GC times
evenly between the young GC's and old GC's and that is not always the
general that policy produces reasonably good results but when that
drive the moving of the boundary, I've seen cases where there are
regressions (i.e., GC ergonomics turned on but worse performance when the
boundary moving is additionally turned on).
On 2/7/2012 9:04 AM, Srinivas Ramakrishna wrote:
> Hi Jon, John, et al. --
> What's the current status of and experience with UseAdaptiveGCBoundary?
> As I recall a (long) while ago there was some performance issue with it,
> I can't recall the specific details.
> Is this flag something you recommend trying out? Are there performance
> sharp-corners that one should watch out for if one were to enable this
> feature ?
> thanks for any tips!
> -- ramki
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