From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1767344AbXDEVkN (ORCPT ); Thu, 5 Apr 2007 17:40:13 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1767349AbXDEVkN (ORCPT ); Thu, 5 Apr 2007 17:40:13 -0400 Received: from mx1.redhat.com ([66.187.233.31]:51466 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1767344AbXDEVkJ (ORCPT ); Thu, 5 Apr 2007 17:40:09 -0400 Message-ID: <46156CA9.3060105@redhat.com> Date: Thu, 05 Apr 2007 17:39:53 -0400 From: Rik van Riel Organization: Red Hat, Inc User-Agent: Thunderbird 1.5.0.7 (X11/20061008) MIME-Version: 1.0 To: Andrew Morton CC: Nick Piggin , Ulrich Drepper , Linux Kernel , Jakub Jelinek , Linux Memory Management Subject: Re: missing madvise functionality References: <46128051.9000609@redhat.com> <461357C4.4010403@yahoo.com.au> <46154226.6080300@redhat.com> <20070405140723.8477e314.akpm@linux-foundation.org> In-Reply-To: <20070405140723.8477e314.akpm@linux-foundation.org> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Andrew Morton wrote: > #if NR_CPUS >= CONFIG_SPLIT_PTLOCK_CPUS > I wonder which way you're using, and whether using the other way changes > things. I'm using the default Fedora config file, which has NR_CPUS defined to 64 and CONFIG_SPLIT_PTLOCK_CPUS to 4, so I am using the split locks. However, I suspect that each 512kB malloced area will share one page table lock with 4 others, so some contention is to be expected. >> For more real world workloads, like the MySQL sysbench one, >> I still suspect that your patch would improve things. >> >> Time to move back to debugging other stuff, though. >> >> Andrew, it would be nice if our patches could cook in -mm >> for a while. Want me to change anything before submitting? > > umm. I took a quick squint at a patch from you this morning and it looked > OK to me. Please send the finalish thing when it is fully baked and > performance-tested in the various regions of operation, thanks. Will do. Ulrich has a test version of glibc available that uses MADV_DONTNEED for free(3), that should test this thing nicely. I'll run some tests with that when I get the time, hopefully next week. -- Politics is the struggle between those who want to make their country the best in the world, and those who believe it already is. Each group calls the other unpatriotic. From mboxrd@z Thu Jan 1 00:00:00 1970 Message-ID: <46156CA9.3060105@redhat.com> Date: Thu, 05 Apr 2007 17:39:53 -0400 From: Rik van Riel MIME-Version: 1.0 Subject: Re: missing madvise functionality References: <46128051.9000609@redhat.com> <461357C4.4010403@yahoo.com.au> <46154226.6080300@redhat.com> <20070405140723.8477e314.akpm@linux-foundation.org> In-Reply-To: <20070405140723.8477e314.akpm@linux-foundation.org> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org Return-Path: To: Andrew Morton Cc: Nick Piggin , Ulrich Drepper , Linux Kernel , Jakub Jelinek , Linux Memory Management List-ID: Andrew Morton wrote: > #if NR_CPUS >= CONFIG_SPLIT_PTLOCK_CPUS > I wonder which way you're using, and whether using the other way changes > things. I'm using the default Fedora config file, which has NR_CPUS defined to 64 and CONFIG_SPLIT_PTLOCK_CPUS to 4, so I am using the split locks. However, I suspect that each 512kB malloced area will share one page table lock with 4 others, so some contention is to be expected. >> For more real world workloads, like the MySQL sysbench one, >> I still suspect that your patch would improve things. >> >> Time to move back to debugging other stuff, though. >> >> Andrew, it would be nice if our patches could cook in -mm >> for a while. Want me to change anything before submitting? > > umm. I took a quick squint at a patch from you this morning and it looked > OK to me. Please send the finalish thing when it is fully baked and > performance-tested in the various regions of operation, thanks. Will do. Ulrich has a test version of glibc available that uses MADV_DONTNEED for free(3), that should test this thing nicely. I'll run some tests with that when I get the time, hopefully next week. -- Politics is the struggle between those who want to make their country the best in the world, and those who believe it already is. Each group calls the other unpatriotic. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org