From: "H.J. Lu" <hjl.tools@gmail.com>
To: Corey Kasten <corey@materialintelligencellc.com>
Cc: gcc@gcc.gnu.org
Subject: Re: Better performance on older version of GCC
Date: Fri, 27 Aug 2010 14:20:00 -0000 [thread overview]
Message-ID: <AANLkTi=BwhajXZCa=yAhN9C0P=Rp-z7WR58nX9eBi90p@mail.gmail.com> (raw)
In-Reply-To: <1282916665.2100.39.camel@MILLC-COREY>
On Fri, Aug 27, 2010 at 6:44 AM, Corey Kasten
<corey@materialintelligencellc.com> wrote:
> Hello all,
>
> I have two computers with two different versions of GCC. Otherwise the
> two systems have identical hardware. I have a processor and memory
> intensive benchmark program which I compile on both systems and I cannot
> understand why the system with older GCC version compiles faster code.
>
> System A has GCC version "4.1.2 20070925 (Red Hat 4.1.2-33)"
> System B has GCC version "4.3.0 20080428 (Red Hat 4.3.0-8)"
>
> I find that the executable compiled on system A runs faster (on both
> systems) than the executable compiled on system B (on both system), by a
> factor about approximately 4 times. I have attempted to play with the
> GCC optimizer flags and have not been able to get System B (with the
> later GCC version) to compile code with any better performance. Could
> someone please help figure this out?
>
Can you try gcc 4.5.1?
--
H.J.
next prev parent reply other threads:[~2010-08-27 13:49 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-08-27 13:50 Corey Kasten
2010-08-27 14:20 ` H.J. Lu [this message]
2010-08-27 14:23 ` Nathan Froyd
2010-08-27 15:03 ` Corey Kasten
2010-08-27 15:40 ` Richard Guenther
2010-08-27 16:29 ` Corey Kasten
2010-08-28 1:06 ` Xinliang David Li
2010-08-28 8:23 ` Andrew Pinski
2010-08-28 10:08 ` Xinliang David Li
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