RFR (7xS): 8071280, 8162928, 8177707, 8177044, 8178148, 8175554, 8178151: Remembered set update/scan improvements

[Mikael Gerdin]

Hi,

On 2017-04-21 03:47, Kim Barrett wrote:
>> On Apr 11, 2017, at 7:30 AM, Thomas Schatzl <thomas.schatzl at oracle.com> wrote:
>>
>> Hi all,
>>
>>   I would like you to ask for reviews of a set of related changes that
>> optimize the way G1 updates/scans/refines cards of the remembered set.
>>
>> […]
>> Here we go:
>>
>> […]
>> 8162928: Micro-optimizations in scanning the remembered sets
>>
>> CR: https://bugs.openjdk.java.net/browse/JDK-8162928
>> Webrev: http://cr.openjdk.java.net/~tschatzl/8162928/webrev/
>>
>> This change removes the use of HeapRegionDCTOC during scanning
>> remembered sets, and uses the faster
>> HeapRegion::oops_on_card_seq_iterate_careful() (measured).
>> HeapRegionDCTOC also depends CMS code which is just bad.
>
> Looks good.

+1

/Mikael

>
> ------------------------------------------------------------------------------
> src/share/vm/gc/g1/g1RemSet.cpp
>  318     r->oops_on_card_seq_iterate_careful<G1ParPushHeapRSClosure, true>(mr, _push_heap_cl);
>
> This will of course need to be updated for my earlier suggested change
> to reorder the template parameters.  I don't need a new webrev for that.
>
> ------------------------------------------------------------------------------
>
>