From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from pigeon.gentoo.org ([208.92.234.80] helo=lists.gentoo.org) by finch.gentoo.org with esmtp (Exim 4.60) (envelope-from ) id 1S9dek-0003qV-Ue for garchives@archives.gentoo.org; Mon, 19 Mar 2012 14:33:55 +0000 Received: from pigeon.gentoo.org (localhost [127.0.0.1]) by pigeon.gentoo.org (Postfix) with SMTP id DEE26E0D5D; Mon, 19 Mar 2012 14:33:26 +0000 (UTC) Received: from mail-bk0-f53.google.com (mail-bk0-f53.google.com [209.85.214.53]) by pigeon.gentoo.org (Postfix) with ESMTP id F0301E0CA1 for ; Mon, 19 Mar 2012 14:31:43 +0000 (UTC) Received: by bkwj4 with SMTP id j4so5191643bkw.40 for ; Mon, 19 Mar 2012 07:31:43 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :content-type:content-transfer-encoding; bh=H4mwS24oIbSxMe0676S0+Z8+9Ku/K+27duw2xFnYcyQ=; b=r3m0pdOu1pOxhUbn/c0GzEjAMnU0yrlcG9D8VWW/QxBqcQQ12xw3vNvBqNERjY99ay C4kpBgI7+FPn2Vl4bxxJCGEoY7WD2hK0+XY4w1vQYQo2JHxHINn4KaZCpQVn5VLzRuAT RFzgwDUViRz6XHD9k5oKfri0Qm50HibAdgNQECk94ELXtvNxgGGpSDaeYSsphCaaKAw0 /7yPVGG2maynE6am6fUBybsrL/DMKOSxFAnSkU3UBO1oorEFt6I/qQay5nEXB/ukC0gh uqG4RO66f81nUj4xYyw6Vhg8ztDJPBUtiTJmNm9id8kIJBy12sOZkasno0hGHaUQZQoH Ro9A== Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-Id: Gentoo Linux mail X-BeenThere: gentoo-user@lists.gentoo.org Reply-to: gentoo-user@lists.gentoo.org MIME-Version: 1.0 Received: by 10.205.132.145 with SMTP id hu17mr4856248bkc.66.1332167503117; Mon, 19 Mar 2012 07:31:43 -0700 (PDT) Received: by 10.204.168.17 with HTTP; Mon, 19 Mar 2012 07:31:43 -0700 (PDT) In-Reply-To: <4F674031.4050203@wht.com.au> References: <20120319132643.Horde.NzbZHrtUV7tPZsOT40nUZ2A@webmail.wht.com.au> <4F674031.4050203@wht.com.au> Date: Mon, 19 Mar 2012 10:31:43 -0400 Message-ID: Subject: Re: [gentoo-user] Changing compilers From: Michael Mol To: gentoo-user@lists.gentoo.org Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable X-Archives-Salt: 802f1e2c-07fe-4216-a1a2-1703e61a079c X-Archives-Hash: f51caab57f76e5c00d280d275125edeb On Mon, Mar 19, 2012 at 10:18 AM, Andrew Lowe wrote: > On 03/19/12 22:02, Michael Mol wrote: >> On Mon, Mar 19, 2012 at 8:32 AM, Mark Knecht wrot= e: >>> On Sun, Mar 18, 2012 at 10:26 PM, Andrew Lowe wrote: >>>> Hi all, >>>> =C2=A0 =C2=A0Has anyone played around with the various "better known" = compilers on >>>> Gentoo? By "better known", I'm referring to gcc, Intel, llvm, pathscal= e. My >>>> situation is that I've just started my PhD which requires me to do Fin= ite >>>> Element Analysis, FEA, and Computational Fluid Dynamics, CFD, and I wa= nt to >>>> find the "best" compiler for the job. Before anyone says "Why bother, = XXX >>>> compiler is only 1 - 2% faster than gcc", in the context of the work I= 'm >>>> doing this 1 - 2% IS important. >>>> >>>> What I'm looking for is any feedback people may have on ability to com= pile >>>> the Gentoo environment, the ability to change compilers easily, gcc-co= nfig >>>> or flags in make.conf, as to whether the compiler/linker can use the >>>> libraries as compiled by gcc on a "standard" gentoo install and so on. >>>> Obviously there is much web trawling to be done to find what other peo= ple >>>> are saying as well. >>>> >>>> Any thoughts, greatly appreciated, >>>> =C2=A0 =C2=A0 =C2=A0 Andrew Lowe >>>> >>>> >>> >>> Think CUDA >> >> Yes. And as a convenient side-effect, it offers a great excuse to >> upgrade your video card with some regularity. The performance of >> mid-grade and high-grade video cards continues to improve rapidly. >> > > =C2=A0 =C2=A0 =C2=A0 =C2=A0Sorry, can't do that, I'm using epic, > > http://tinyurl.com/83l5o3z > > which currently ranks at 151 in the top 500 list :) It's amazing how > fast this list changes, 6 months ago, this machine was at 107 and 6 > months before that 87. That does change things a bit. I don't know Epic's structure or their upgrade plans, but if you're confident it's not going to have GPGPU capabilities, then CUDA and OpenCL are less useful for you. OpenCL, at least, still handles per-CPU and per-node job dispatching, though. And that's still likely to be useful for performing on huge matrices. To answer your original question: No, I haven't done much with anything other than gcc on Gentoo. What you *should* do is grab each compiler (trial versions, if necessary) and test them to find which gives you the best results. It's my understanding PhD programs involve getting things done right, not so much quickly or easily. Best to be methodical about it. --=20 :wq