review for 7029167: add support for conditional card marks
vladimir.kozlov at oracle.com
Wed Mar 30 17:24:55 PDT 2011
Looks good then. We may need to switch it ON for Nightly testing.
Tom Rodriguez wrote:
> On Mar 30, 2011, at 5:03 PM, Vladimir Kozlov wrote:
>> what about arraycopy stubs?
> I don't think they are necessary. This is really about the performance of concurrent algorithms that are doing a lot of field updates, not eliminating all redundant card marks.
>> Tom Rodriguez wrote:
>>> 7029167: add support for conditional card marks
>>> Repeated updates to the card table can be a source of contention on
>>> multiprocessor machines that can greatly inhibit scalability. This
>>> adds support in C2 for conditional card marks. Tested with jbb and
>>> CTW. At some point this should be turned on automatically when multi
>>> socket machines are detected but that's covered under another bug as
>>> is C1 support.
More information about the hotspot-compiler-dev