Article: Nehalem Performance Preview
By: Paul (no.delete@this.thanks.com), April 12, 2009 12:53 am
Room: Moderated Discussions
Henrik S (henrik.stahl@nospam.oracle.nothanks.com) on 4/12/09 wrote:
---------------------------
>No difference between Windows 2003 and 2008. We get slightly higher scores (1%?)
>on Windows than Linux, something we believe can be partially attributed to a gcc
>compiler optimization we don't use on Linux (omit_frame_pointer), but we haven't
>analyzed it lately so it may be something else (if any Linux gurus here feel like
>figuring that one out, I'd be happy to help them get started).
I think that omit-frame-pointer pointer has been part of -O for GCC for a while, a lot of work was put in to make debugging possible on x86 without the frame pointer.
What version of GCC are you using? To be competitive with the MS compiler you'll need to be bang up to date with the 4.3 series.
The other thing it would be interesting to do is to compile your codebase with the Intel C++ compiler, you can get evaluation versions of this and if your code compiles with both GCC and MSVC++ then you ought to be able to get it past Intel C++ without much effort.
A 1% difference might not even be the compiler it could be some difference in CPU affinity, or slighly non optimal case in the VM or something.
Recent versions of VTune have a library you can link your code to which allows you to teach VTune about JIT compiled code, it could be instructive to try that as well.
---------------------------
>No difference between Windows 2003 and 2008. We get slightly higher scores (1%?)
>on Windows than Linux, something we believe can be partially attributed to a gcc
>compiler optimization we don't use on Linux (omit_frame_pointer), but we haven't
>analyzed it lately so it may be something else (if any Linux gurus here feel like
>figuring that one out, I'd be happy to help them get started).
I think that omit-frame-pointer pointer has been part of -O for GCC for a while, a lot of work was put in to make debugging possible on x86 without the frame pointer.
What version of GCC are you using? To be competitive with the MS compiler you'll need to be bang up to date with the 4.3 series.
The other thing it would be interesting to do is to compile your codebase with the Intel C++ compiler, you can get evaluation versions of this and if your code compiles with both GCC and MSVC++ then you ought to be able to get it past Intel C++ without much effort.
A 1% difference might not even be the compiler it could be some difference in CPU affinity, or slighly non optimal case in the VM or something.
Recent versions of VTune have a library you can link your code to which allows you to teach VTune about JIT compiled code, it could be instructive to try that as well.
Topic | Posted By | Date |
---|---|---|
Nehalem review up | David Kanter | 2009/04/07 02:43 AM |
Nehalem review up | noone | 2009/04/07 05:48 AM |
Strange jbb on Harpertown | Henrik S | 2009/04/07 07:29 AM |
Strange jbb on Harpertown | David Kanter | 2009/04/07 10:19 AM |
Strange jbb on Harpertown | Henrik S | 2009/04/07 08:33 PM |
Strange jbb on Harpertown | Chris | 2009/04/07 11:54 PM |
Strange jbb on Harpertown | Henrik S | 2009/04/08 01:40 AM |
Nehalem review up | Vincent Diepeveen | 2009/04/07 07:34 AM |
Nehalem review up | Jack | 2009/04/09 03:51 PM |
Nehalem review up | Vincent Diepeveen | 2009/04/10 12:58 AM |
Nehalem review up | Michael S | 2009/04/10 02:45 AM |
Nehalem review up | EduardoS | 2009/04/10 06:01 AM |
Nehalem review up | Michael S | 2009/04/10 06:56 AM |
Nehalem review up | Eugene Nalimov | 2009/04/10 08:12 AM |
Choice of C compiler doesn't matter much for Java... | Henrik S | 2009/04/10 09:10 AM |
Choice of C compiler doesn't matter much for Java... | EduardoS | 2009/04/10 01:49 PM |
Choice of C compiler doesn't matter much for Java... | Henrik S | 2009/04/11 06:13 AM |
Choice of C compiler doesn't matter much for Java... | EduardoS | 2009/04/11 10:30 AM |
Large pages | David Kanter | 2009/04/11 01:02 PM |
Choice of C compiler doesn't matter much for Java... | Henrik S | 2009/04/11 10:06 PM |
Choice of C compiler doesn't matter much for Java... | Paul | 2009/04/12 12:53 AM |
Choice of C compiler doesn't matter much for Java... | iz | 2009/04/12 01:59 AM |
Choice of C compiler doesn't matter much for Java... | Henrik S | 2009/04/12 06:37 AM |
Choice of C compiler doesn't matter much for Java... | EduardoS | 2009/04/12 07:08 AM |
Choice of C compiler doesn't matter much for Java... | Henrik S | 2009/04/12 08:25 AM |
Choice of C compiler doesn't matter much for Java... | EduardoS | 2009/04/12 04:24 PM |
Choice of C compiler doesn't matter much for Java... | Henrik S | 2009/04/12 09:18 PM |
Thread costs | David Kanter | 2009/04/12 11:12 PM |
Thread costs | Henrik S | 2009/04/14 01:08 PM |
Choice of C compiler doesn't matter much for Java... | Michael S | 2009/04/11 07:53 AM |
Choice of C compiler doesn't matter much for Java... | Henrik S | 2009/04/11 10:08 PM |
Nehalem review up | Vincent Diepeveen | 2009/04/11 03:50 PM |
Nehalem review up | Michael S | 2009/04/11 04:12 PM |
Nehalem review up | Vincent Diepeveen | 2009/04/12 02:01 AM |
Nehalem review up | Michael S | 2009/04/12 04:07 AM |
Nehalem review up | rwessel | 2009/04/07 01:01 PM |
Nehalem review up | slacker | 2009/04/08 08:11 AM |
Energy vs. power | David Kanter | 2009/04/08 09:11 AM |
Energy vs. power | Vincent Diepeveen | 2009/04/10 01:08 AM |
Energy vs. power | slacker | 2009/04/10 08:26 AM |
Energy vs. power | RagingDragon | 2009/04/10 09:19 AM |
Energy vs. power | David Kanter | 2009/04/10 10:47 AM |
Energy vs. power | Jack | 2009/04/10 03:44 PM |
Energy vs. power | slacker | 2009/04/10 06:00 PM |
Energy vs. power | Jack | 2009/04/10 06:31 PM |
Energy vs. power | David Kanter | 2009/04/10 11:16 PM |
Nehalem review up | rwessel | 2009/04/08 01:32 PM |
Minor font issue | gpriatko | 2009/04/07 03:35 PM |
Minor HTML issue | David Kanter | 2009/04/07 08:38 PM |
Minor HTML issue | David Kanter | 2009/04/07 08:39 PM |
Good work, i look forward to linux and SP2 numbers (NT) | PiedPiper | 2009/04/08 12:52 AM |
Nehalem review up | Joe Chang | 2009/04/10 02:59 AM |