RFR (XXL): 8213108: Improve work distribution during remembered set scan

[Leo Korinth]

Hi!

Sorry for taking so very long time to review. In g1RemSet.cpp:

* uint const num_chunks = (uint)align_up((size_t)num_regions << 
HeapRegion::LogCardsPerRegion, G1ClearCardTableTask::chunk_size()) / 
G1ClearCardTableTask::chunk_size();

make sure the (uint) cast is done after the division (so not to cast 
away bits).

* initialize _scan_chunks_shift in initializer list to silence eclipse 
warnings.

* in ::memset(_region_scan_chunks, false, _max_regions * 
_scan_chunks_per_region); please multiply last argument with 
sizeof(*_region_scan_chunks)

Otherwise it looks very good to my untrained eyes. I gave you a few 
extra ideas off list, you may add some of them if you like.

Thanks,
Leo




On 17/06/2019 21:09, Kim Barrett wrote:
>> On Jun 17, 2019, at 8:23 AM, Thomas Schatzl <thomas.schatzl at oracle.com> wrote:
>> New webrev:
>> http://cr.openjdk.java.net/~tschatzl/8213108/webrev.1_to_2/ (diff)
>> http://cr.openjdk.java.net/~tschatzl/8213108/webrev.2/ (full)
>>
>> Testing: hs-tier1-3
>>
>> Thanks,
>>   Thomas
> 
> Looks good.
>