Request for review (S): 8005972: ParNew should not update the tenuring threshold when promotion failed has occurred

[Srinivas Ramakrishna]

Hi Bengt --

The change looks reasonable, but I have a comment and a follow-up question.

Not your change, but I'd elide the "half the real survivor size" since it's
really a configurable parameter based on TargetSurvivorRatio with default
half.
I'd leave the comment as "set the new tenuring threshold and desired
survivor size".

I'm curious though, as to what performance data prompted this change, and
whether it might make sense, upon a promotion failure to do something about
the tenuring threshold for the next scavenge (i.e. for example make the
tenuring threshold half of its current value as a reaction to the fact that
promotion failed). Is it currently left at its previous value or is it
asjusted back to the default max value (which latter may be the wrong thing
to do) or something else?

-- ramki

On Thu, Jan 10, 2013 at 1:30 AM, Bengt Rutisson
<bengt.rutisson at oracle.com>wrote:

>
> Hi everyone,
>
> Could I have a couple of reviews for this small change to make DefNew and
> ParNew be more consistent in the way they treat the tenuring threshold:
>
> http://cr.openjdk.java.net/~**brutisso/8005972/webrev.00/<http://cr.openjdk.java.net/%7Ebrutisso/8005972/webrev.00/>
>
> Thanks,
> Bengt
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://mail.openjdk.org/pipermail/hotspot-gc-dev/attachments/20130110/da55c26d/attachment.htm>