From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jeff King Subject: Re: [PATCH 2/4] bump rename limit defaults (again) Date: Sun, 20 Feb 2011 05:10:24 -0500 Message-ID: <20110220101024.GC988@sigill.intra.peff.net> References: <20110219101936.GB20577@sigill.intra.peff.net> <20110219102128.GB22508@sigill.intra.peff.net> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Cc: Linus Torvalds , Junio C Hamano , Martin Langhoff , Git Mailing List To: Piotr Krukowiecki X-From: git-owner@vger.kernel.org Sun Feb 20 11:10:32 2011 Return-path: Envelope-to: gcvg-git-2@lo.gmane.org Received: from vger.kernel.org ([209.132.180.67]) by lo.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1Pr6FL-0003nR-S6 for gcvg-git-2@lo.gmane.org; Sun, 20 Feb 2011 11:10:32 +0100 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752733Ab1BTKK1 (ORCPT ); Sun, 20 Feb 2011 05:10:27 -0500 Received: from xen6.gtisc.gatech.edu ([143.215.130.70]:44521 "EHLO peff.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752643Ab1BTKK0 (ORCPT ); Sun, 20 Feb 2011 05:10:26 -0500 Received: (qmail 16649 invoked by uid 111); 20 Feb 2011 10:10:26 -0000 Received: from 99-108-226-0.lightspeed.iplsin.sbcglobal.net (HELO sigill.intra.peff.net) (99.108.226.0) (smtp-auth username relayok, mechanism cram-md5) by peff.net (qpsmtpd/0.40) with ESMTPA; Sun, 20 Feb 2011 10:10:26 +0000 Received: by sigill.intra.peff.net (sSMTP sendmail emulation); Sun, 20 Feb 2011 05:10:24 -0500 Content-Disposition: inline In-Reply-To: Sender: git-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org Archived-At: On Sat, Feb 19, 2011 at 06:54:47PM +0100, Piotr Krukowiecki wrote: > On Sat, Feb 19, 2011 at 11:21 AM, Jeff King wrote: > > Let's bump the diff/merge default limits from 200/500 to > > 400/1000. Those are 2 seconds and 10 seconds respectively on > > my modern hardware. > > Just curious - what is your modern hardware? It's a Core i7 840QM. So it's a measly 1.8GHz, but it turboboosts up to 3.2GHz on a single-threaded process. The multiple cores are irrelevant for this timing, as it's very single-threaded[1]. The process used in the tens of megabytes of memory, so I think memory size is irrelevant. It was very CPU bound in my tests. -Peff [1] Actually, this is one place where multi-threading the algorithm would be very easy. It's literally an m*n double-loop, seeing which of each "n" sources matches each "m" destination best, and the expensive bit is comparing a source and dest. So you could parallelize score calculation up to m*n ways, then just sort the result for each dest.