Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1422915AbWJaH7t (ORCPT ); Tue, 31 Oct 2006 02:59:49 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1422799AbWJaH7t (ORCPT ); Tue, 31 Oct 2006 02:59:49 -0500 Received: from emailer.gwdg.de ([134.76.10.24]:36059 "EHLO emailer.gwdg.de") by vger.kernel.org with ESMTP id S1422915AbWJaH7s (ORCPT ); Tue, 31 Oct 2006 02:59:48 -0500 Date: Tue, 31 Oct 2006 08:59:22 +0100 (MET) From: Jan Engelhardt To: Zachary Amsden cc: Linux Kernel Mailing List Subject: Re: 2.6.18 is problematic in VMware In-Reply-To: <45463B7D.8050002@vmware.com> Message-ID: References: <45463B7D.8050002@vmware.com> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII X-Spam-Report: Content analysis: 0.0 points, 6.0 required _SUMMARY_ Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1450 Lines: 38 >> I have observed a strange slowdown with the 2.6.18 kernel in VMware. This >> happened both with the SUSE flavor and with the FC6 installer CD (which I >> am trying right now). In both cases, the kernel "takes its time" after the >> following text strings: >> >> * Checking if this processor honours the WP bit even in supervisor mode... >> Ok. >> * Checking 'hlt' instruction... OK. >> >> What's with that? > > Thanks. It is perhaps the jiffies calibration taking a while because of the > precise timing loop. Are you reasonably confident that it is a regression in > performance over 2.6.17? Yes. I am not exactly sure if it's something in jiffies calibration (because of the 'WP bit/supervisor' thing too), so maybe I thought it was the newly-introduced SMP alternatives. I gotta check that. > The boot sequence is pretty complicated, and a lot of > it is difficult / slow to virtualize, so it could just be alternate timing > makes the boot output appear to stall, when in fact the raw time is still about > the same. I will run some experiments. Booting with 'time' shows that the virtual time increases as usual, i.e. [ 9.00] checking if wp bit... [15.00] next message here -`J' -- - 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/