From mboxrd@z Thu Jan 1 00:00:00 1970 From: Linus Torvalds Subject: Re: [PATCH 3/2] Avoid unnecessary strlen() calls Date: Mon, 19 Mar 2007 21:45:38 -0700 (PDT) Message-ID: References: <7v8xdunavr.fsf@assigned-by-dhcp.cox.net> <20070320032947.GA29145@spearce.org> <20070320034020.GB29145@spearce.org> <20070320041843.GA29288@spearce.org> Mime-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Cc: Johannes Schindelin , Junio C Hamano , Nicolas Pitre , Morten Welinder , Git Mailing List To: "Shawn O. Pearce" X-From: git-owner@vger.kernel.org Tue Mar 20 05:46:21 2007 Return-path: Envelope-to: gcvg-git@gmane.org Received: from vger.kernel.org ([209.132.176.167]) by lo.gmane.org with esmtp (Exim 4.50) id 1HTWEn-0002xl-1Y for gcvg-git@gmane.org; Tue, 20 Mar 2007 05:46:21 +0100 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S964976AbXCTEqB (ORCPT ); Tue, 20 Mar 2007 00:46:01 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S933988AbXCTEqA (ORCPT ); Tue, 20 Mar 2007 00:46:00 -0400 Received: from smtp.osdl.org ([65.172.181.24]:46103 "EHLO smtp.osdl.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933987AbXCTEqA (ORCPT ); Tue, 20 Mar 2007 00:46:00 -0400 Received: from shell0.pdx.osdl.net (fw.osdl.org [65.172.181.6]) by smtp.osdl.org (8.12.8/8.12.8) with ESMTP id l2K4jdcD022671 (version=TLSv1/SSLv3 cipher=EDH-RSA-DES-CBC3-SHA bits=168 verify=NO); Mon, 19 Mar 2007 21:45:40 -0700 Received: from localhost (shell0.pdx.osdl.net [10.9.0.31]) by shell0.pdx.osdl.net (8.13.1/8.11.6) with ESMTP id l2K4jc85025903; Mon, 19 Mar 2007 20:45:39 -0800 In-Reply-To: <20070320041843.GA29288@spearce.org> X-Spam-Status: No, hits=-0.977 required=5 tests=AWL,OSDL_HEADER_SUBJECT_BRACKETED X-Spam-Checker-Version: SpamAssassin 2.63-osdl_revision__1.119__ X-MIMEDefang-Filter: osdl$Revision: 1.176 $ X-Scanned-By: MIMEDefang 2.36 Sender: git-owner@vger.kernel.org Precedence: bulk X-Mailing-List: git@vger.kernel.org Archived-At: On Tue, 20 Mar 2007, Shawn O. Pearce wrote: > > I tested both patches on a PowerPC G4. (Apple PowerBook, 1.5 GHz) > Running on Mac OS X 10.4.8. > > Might be more of a Linux<->Darwin thing; perhaps my isspace is > significantly slower than yours is... after all my mmap runs > like a PC from the 1980s... ;-) No, we do a git-specific isspace(). But yeah, a G4 will explain the thing even more than a P4 would. The G4 really isn't a very good uarch compared to the modern x86 ones. Not aggressively out-of-order with deep instruction queues and I don't think it does basically any memop re-ordering at all. I know Apple used to claim that they were the fastest PC around (both with the G4 and the G5), but let's face it, they lied. The closer to in-order you are, the more instruction scheduling in sw tends to matter. Linus