RFR (M): 8201172: Parallelize Remset Tracking Update Before Rebuild phase
stefan.johansson at oracle.com
Tue Apr 10 12:29:56 UTC 2018
On 2018-04-09 13:16, Thomas Schatzl wrote:
> Hi all,
> can I have reviews for this straightforward change that improves the
> "Remset Tracking Update Before Rebuild" phase of the Remark pause?
> Performance of this phase has not been a big issue, with ~3000 regions
> you get around 1ms of time taken, but now it's even faster and
> hopefully if run with 30k regions, there are no nasty suprises (or not
> as nasty at least).
> Determining the number of threads to use has been done by doing a few
> measurements and tests and look at which point there does not seem to
> be any more scaling (i.e. the noise seems higher than the
> improvements), and the pause time much smaller than a millisecond.
Looks good, just a few minor things:
1108 G1UpdateRemSetTrackingBeforeRebuild cl(_g1h, _cm, &_cl);
Using the same names for all closures and and having
num_selected_for_rebuild in both the task and the closure, makes this
code a bit hard to follow. I suggest calling the task member
_total_selected_for_rebuild and also have the getter name match the
member for the closure.
For the closures I'm fine with the members being named _cl, but it would
help if the instance above were name something else, like rebuild.
> hs-tier 1-3
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