Review request (S): 7179517 Enable NUMA by default on NUMA hardware

Vladimir Kozlov vladimir.kozlov at
Mon Jul 2 19:31:08 UTC 2012

Hi Jasper,

Why you added #include "runtime/os.hpp"? It is compiled without it (it is 
included in an other header file). You would not be able to compile this file 
since it define methods declared in os.hpp.

UseNUMAInterleaving is set 'true' only for Parallel GC in arguments.cpp. New 
code set it 'true' for all GCs which may cause problem. Also there is solaris 
code which depends on this flag and it is not set in this changes.


Jesper Wilhelmsson wrote:
> I have updated the webrev with a Solaris patch as well. It's the same 
> URL, just do a reload in your browser.
> I'm not a Solaris native either, so regarding testing I have asked the 
> performance team to look extra close on Solaris to make sure it behaves 
> as expected.
> /Jesper
> On 2012-07-02 19:26, Vladimir Kozlov wrote:
>> That question was not for you but for Jesper.
>> Vladimir
>> Eric Caspole wrote:
>>> I am hoping one of you guys can do it - I have never used Solaris and I
>>> don't know if there is any special thing to take into account there.
>>> On Jul 2, 2012, at 12:07 PM, Vladimir Kozlov wrote:
>>>> Why there is no changes for Solaris?
>>>> Vladimir
>>>> On 7/2/12 3:57 AM, Jesper Wilhelmsson wrote:
>>>>> Hi,
>>>>> This change is to turn on UseNUMA per default on NUMA hardware. It has
>>>>> been contributed by Eric Caspole. I'm fine with
>>>>> the change but we need at least one official reviewer.
>>>>> Webrev:
>>>>> Testing:
>>>>> I ran it through JPRT and did some local sanity testing.
>>>>> Eric has tested this on SPECjbb2005 and SPECjvm2008 with a variety 
>>>>> of heap
>>>>> sizes and it is never worse than the current
>>>>> default. In some cases, especially with Windows, running a test 
>>>>> with the
>>>>> current default and getting bad NUMA placement
>>>>> will be about 3x slower than the +UseNUMA score.
>>>>> The performance team are involved to perform some larger scale 
>>>>> testing.

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