[parsec-users] the OpenMP version blackscholes has No speedup when has more than 4 cores

Eric Lu eirc.lew at gmail.com
Mon Oct 14 22:13:22 EDT 2013


Yes, the performance means speedup, I run blackscholes with simlarge input
not native inputs.

I will read the paper you recommended.

Thanks!

Eric


On Tue, Oct 15, 2013 at 9:58 AM, kishore kumar <kishoreguptaos at gmail.com>wrote:

> What do you mean by poor performance? Is it speedup? I guess that you run
> blackscholes with native inputs. With large inputs, blackscholes main
> thread does more work (serial execution -- reading input file, etc.,)
> compared to the worker threads (parallel execution). Around 95% of the
> entire execution time, you only see one thread, i.e., main thread. May be
> you want to read "Thread Reinforcer: Dynamically Determining Number of
> Threads" paper.
>
> Thanks.
>
> Best,
> Kishore Kumar Pusukuri
> http://www.cs.ucr.edu/~kishore
>
>
> On Mon, Oct 14, 2013 at 6:34 PM, Eric Lu <eirc.lew at gmail.com> wrote:
>
>> Hi,
>>
>> I run PARSEC2.1 on Intel E7520 machine, the os is centos6.3, the gcc-4.7
>> compiler. The machine has 32 cores in total, and the results seems
>> blackscholes has too poor performance.
>> The data shows as follow:
>> OpenMP
>> proc blackscholes
>> 1 0.998269
>> 2 1.80499
>> 4 1.763301
>> 8 1.550916
>> 16 1.542871
>> 32 2.508076
>>
>>
>>
>> Best Regards!
>>
>>
>> Eric
>>
>> _______________________________________________
>> parsec-users mailing list
>> parsec-users at lists.cs.princeton.edu
>> https://lists.cs.princeton.edu/mailman/listinfo/parsec-users
>>
>>
>
> _______________________________________________
> parsec-users mailing list
> parsec-users at lists.cs.princeton.edu
> https://lists.cs.princeton.edu/mailman/listinfo/parsec-users
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.cs.princeton.edu/pipermail/parsec-users/attachments/20131015/a161e6c3/attachment.html>


More information about the parsec-users mailing list