From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from lists.gentoo.org ([140.105.134.102] helo=robin.gentoo.org) by nuthatch.gentoo.org with esmtp (Exim 4.50) id 1Ef6Cy-0005Lc-D5 for garchives@archives.gentoo.org; Thu, 24 Nov 2005 01:47:32 +0000 Received: from robin.gentoo.org (localhost [127.0.0.1]) by robin.gentoo.org (8.13.5/8.13.5) with SMTP id jAO1kaOq012146; Thu, 24 Nov 2005 01:46:36 GMT Received: from mail-ihug.icp-qv1-irony2.iinet.net.au (ihug-mail.icp-qv1-irony2.iinet.net.au [203.59.1.196]) by robin.gentoo.org (8.13.5/8.13.5) with ESMTP id jAO1glMk017769 for ; Thu, 24 Nov 2005 01:42:49 GMT Received: from 203-59-213-82.dyn.iinet.net.au (HELO moriah.localdomain) ([203.59.213.82]) by mail-ihug.icp-qv1-irony2.iinet.net.au with ESMTP; 24 Nov 2005 09:42:25 +0800 X-BrightmailFiltered: true X-Brightmail-Tracker: AAAAAA== Received: from localhost (localhost [127.0.0.1]) by moriah.localdomain (Postfix) with ESMTP id 7EF721A5EB8 for ; Thu, 24 Nov 2005 09:42:24 +0800 (WST) Received: from moriah.localdomain ([127.0.0.1]) by localhost (moriah.localdomain [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 24996-03 for ; Thu, 24 Nov 2005 09:42:22 +0800 (WST) Received: from localhost (localhost [127.0.0.1]) by moriah.localdomain (Postfix) with ESMTP id BCFA668AC for ; Thu, 24 Nov 2005 09:42:22 +0800 (WST) Subject: Re: changing CHOST in stage3 (was : [gentoo-user] default stage3) From: "W.Kenworthy" To: gentoo-user@lists.gentoo.org In-Reply-To: References: <4382B549.1020402@mid.email-server.info> <438404E0.5000507@mid.email-server.info> Content-Type: text/plain Date: Thu, 24 Nov 2005 09:42:21 +0800 Message-Id: <1132796541.23570.21.camel@localhost> Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-Id: Gentoo Linux mail X-BeenThere: gentoo-user@gentoo.org Reply-to: gentoo-user@lists.gentoo.org Mime-Version: 1.0 X-Mailer: Evolution 2.2.3 Content-Transfer-Encoding: 7bit X-Virus-Scanned: amavisd-new at localdomain X-Archives-Salt: f5154146-bdbf-4e48-ae92-cc2fa30e218d X-Archives-Hash: 55ec647e8cc356d04d790a97a017fdc3 To explain, keep in mind that optimisation and chost are two different things. i386 is a "lowest common denominator" instruction set that will run on most 386 and above x86 processors. i4/5/686 adds few specialised instructions and I believe the compiler is able to use them to produce faster code in some cases. The downside is the loss of compatibility - apparent if you switch processors. Is the system faster - my tests (done ages ago now) say yes, but not by much and its highly dependent on the actual code/data in use at the time. Generally, you will get more gain by smarter configuration, better software etc. Thats not to say optimised CFLAGS and compiler choices wont give a useful speedup, especially when crunching data. It just wont turn a 667Mhz P3 into the equivalent 1G P3 - I know I recently tried to "get a little more" out of one :) BillK On Wed, 2005-11-23 at 21:24 -0400, Robin wrote: > > > Wouldn't leaving the CHOST at > > > "i386-pc-linux-gnu" build unoptimized binaries? > > > > No. > > > > Alexander Skwar > > Thanks for that. My CHOST flag is set to i386-pc-linux-gnu even though > it is not. Just a piece of mind I guess not building unoptimized > binaries. > -- gentoo-user@gentoo.org mailing list