Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Mon, 18 Mar 2002 19:29:04 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Mon, 18 Mar 2002 19:28:54 -0500 Received: from hq.fsmlabs.com ([209.155.42.197]:60940 "EHLO hq.fsmlabs.com") by vger.kernel.org with ESMTP id ; Mon, 18 Mar 2002 19:28:51 -0500 From: Cort Dougan Date: Mon, 18 Mar 2002 17:27:05 -0700 To: "David S. Miller" Cc: torvalds@transmeta.com, linux-kernel@vger.kernel.org Subject: Re: 7.52 second kernel compile Message-ID: <20020318172705.O4783@host110.fsmlabs.com> In-Reply-To: <20020318153637.J4783@host110.fsmlabs.com> <20020318.162217.44270627.davem@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.2.5i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org It would be easy to do with the debug registers on PPC but they're supervisor level only. Users have no need to profile their code, after all. A logic analyzer would be really handy here. Dave, think you can swing one? :) I ended up using averages for my tests with the PPC when doing the MM optimizations. Wall-clock time tells you if you did a good thing or not, but not what it was that you actually did :) Any suggestions for a structure, Dave? } On Mon, 18 Mar 2002, Cort Dougan wrote: } > The cycle timer in this case is about 16.6MHz. } } Oh, you're cycle timer is too slow to be interesting, apparently ;( } } We could modify the test program to use more portably timing functions } and doing the TLB accesses several times over. While this would get } us something more reasonable on PPC, and be more portable, the results } would be a bit less accurate because we'd be dealing effectively with } averages instead of real cycle count samples. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/