From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S268842AbUHLWYp (ORCPT ); Thu, 12 Aug 2004 18:24:45 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S268840AbUHLWYo (ORCPT ); Thu, 12 Aug 2004 18:24:44 -0400 Received: from gprs214-76.eurotel.cz ([160.218.214.76]:63110 "EHLO amd.ucw.cz") by vger.kernel.org with ESMTP id S268842AbUHLWYP (ORCPT ); Thu, 12 Aug 2004 18:24:15 -0400 Date: Fri, 13 Aug 2004 00:23:48 +0200 From: Pavel Machek To: kernel list Subject: is_head_of_free_region slowing down swsusp Message-ID: <20040812222348.GA10791@elf.ucw.cz> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline X-Warning: Reading this can be dangerous to your mental health. User-Agent: Mutt/1.5.5.1+cvs20040105i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Hi! is_head_of_free_region with count_and_copy_zone results results in pretty nasty O(number_of_free_regions^2) behaviour, and some users see cpu spending 40 seconds there :-(. Actually count_and_copy_zone would probably be happy with "is_free_page()". I asked Lukas (who is seeing this problem) to kill locking from is_head_of_free_region [we are running singlethreaded at this point, so it should be ok]. Do you have any other ideas? Pavel -- People were complaining that M$ turns users into beta-testers... ...jr ghea gurz vagb qrirybcref, naq gurl frrz gb yvxr vg gung jnl!