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

Jesper Wilhelmsson jesper.wilhelmsson at
Tue Jul 3 10:54:15 UTC 2012

Hi Vladimir,

My IDE wanted me to add os.hpp, I have removed it now.
I have added UseNUMAInterleaving so that the Solaris patch is identical to the 
linux patch.
New webrev (same link as before):

I'm not sure how to handle Solaris though. It won't get the same amount of 
testing as the other platforms. The latest patch has not passed trough JPRT 
yet, I get weird failures. The failures are not on Solaris so I don't see how 
they can be related to this change.

On 2012-07-02 21:31, Vladimir Kozlov wrote:
> 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.
> Thanks,
> Vladimir
> 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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