RFR(XS) 8059780: SPECjvm2008-MPEG performance regressions on x64 platforms
vladimir.kozlov at oracle.com
Mon Nov 3 17:18:50 UTC 2014
Thank you, Igor
On 11/1/14 12:29 AM, Igor Veresov wrote:
> Looks fine to me.
> On Oct 31, 2014, at 2:55 PM, Vladimir Kozlov <vladimir.kozlov at oracle.com> wrote:
>> We found performance regression (3-5%) on x64 after changes 8052081  were pushed. It is caused by changes in lcm.cpp. Those changes were done because Atom is in-order cpu and some benchmarks on Atom showed benefit from these changes.
>> But Atom is not our core platform and the regression is big.
>> Backout changes made in lcm.cpp in jdk9 and 8u40 (8052081 was backported to 8u40).
>> We have RFEs to improve block's instructions order which may help both platforms:
>> Tested with SPECjvm2008-mpegaudio.
>>  https://bugs.openjdk.java.net/browse/JDK-8052081
More information about the hotspot-compiler-dev