RFR: 8033426: Scale initial NewSize using NewRatio if not set on command line

Jesper Wilhelmsson jesper.wilhelmsson at oracle.com
Mon Feb 3 16:50:18 UTC 2014

Hi Stefan,

Have you looked at how this change plays with the ergonomics for NewSize in 
Arguments::set_cms_and_parnew_gc_flags()? That code will also use NewRatio to 
scale NewSize, but if running with a large CMSYoungGenPerWorker it may end up 
with a larger NewSize. Looks like your change will handle it well, but it would 
be nice with some test to verify it going forward.

Anyways, looks good to me.
Ship it!

Stefan Johansson skrev 3/2/14 4:40 PM:
> Hi,
> Can I have a couple of reviews for this enhancement:
> https://bugs.openjdk.java.net/browse/JDK-8033426
> Webrev:
> http://cr.openjdk.java.net/~sjohanss/8033426/webrev.00/
> Summary:
> Currently the initial young generation size is the same as the minimum. If not
> using large pages this will be 1.5M for the default collector regardless of how
> large the whole heap is. The proposed change is to scale the initial young size
> the same way the maximum young size is scaled, using the NewRatio parameter.
> Note:
> This change has been out on review as part of the fix for JDK-8028498, but after
> discussions we have decided take another approach for that bug.
> Testing:
> * JPRT
> * GC tests in jtreg
> Thanks,
> Stefan

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