RFR(XS): 8015244: G1: Verification after a full GC is incorrectly placed
thomas.schatzl at oracle.com
Fri May 24 08:09:52 UTC 2013
On Wed, 2013-05-22 at 16:20 -0700, John Cuthbertson wrote:
> Hi Everyone,
> Can I have a couple of volunteers look over this small fix? The webrev
> can be found at: http://cr.openjdk.java.net/~johnc/8015244/webrev.0/
> While investigating some additional verification code for "7145569: G1:
> optimize nmethods scanning", I realized that the verification that
> occurs after a full GC is misplaced. I think it should come after the
> rebuilding of the RSets and verify the rebuilt RSets. Verifying the
> RSets before the full GC is less interesting and potentially wasteful so
> I placed the RSet verification during full GCs under control of an
> additional diagnostic flag.
> These aren't true performance numbers but when I ran GCOld with the new
> flag enabled (1G heap), I saw an increase in full GC times of around 4%
> on my workstation (VerifyBefore and VerifyAfter were both enabled).
Looks good. Minor issues:
- there is a typo in the description of the new flag: verfiying instead
- could you spell out "rset" in the description as it is done most
commonly so in other descriptions?
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