RFR (L): 8058354: SPECjvm2008-Derby -2.7% performance regression on Solaris-X64 starting with 9-b29

Jon Masamitsu jon.masamitsu at oracle.com
Tue Feb 3 18:32:18 UTC 2015


On 02/03/2015 02:27 AM, Thomas Schatzl wrote:
> Hi Jon,
>
>    thanks for the comments. I incorporated all of them in the latest
> webrev at
>
> http://cr.openjdk.java.net/~tschatzl/8058354/webrev.1/ (full)
> http://cr.openjdk.java.net/~tschatzl/8058354/webrev.0_to_1/ (diff)

Looks good.

>
> There is also a small change to the WhiteBox class that I originally
> forgot to ask reviews for because it is tracked in the root directory:
>
> http://cr.openjdk.java.net/~tschatzl/8058354/webrev.hs-gc.1/

Also looks good.

>
> One comment further down.
>
> On Fri, 2015-01-30 at 14:55 -0800, Jon Masamitsu wrote:
>> Thomas,
>>
>> http://cr.openjdk.java.net/~tschatzl/8058354/webrev/src/share/vm/gc_implementation/g1/g1CollectedHeap.cpp.frames.html
>>
>> Please verify that this should be a call to the _unaligned version.
>>
>>> 1840   size_t const commit_size = os::page_size_for_region_unaligned(size, 1);
> Yes. It ensures that as soon as the given size is larger than a large
> page, try to use large pages (if they are enabled).
>
> This is the same behavior as in 9b28.
>
> If we used os::page_size_for_region_aligned(), we would only try to use
> large pages in case the given size is exactly a multiple of large page
> size.

Thanks for checking.

Reviewed.

Jon

>
> Thanks,
>    Thomas
>
>



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