From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751847AbWHNFFE (ORCPT ); Mon, 14 Aug 2006 01:05:04 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751850AbWHNFFD (ORCPT ); Mon, 14 Aug 2006 01:05:03 -0400 Received: from amsfep17-int.chello.nl ([213.46.243.15]:48905 "EHLO amsfep18-int.chello.nl") by vger.kernel.org with ESMTP id S1751847AbWHNFFB (ORCPT ); Mon, 14 Aug 2006 01:05:01 -0400 Subject: Re: [RFC][PATCH 2/9] deadlock prevention core From: Peter Zijlstra To: Andrew Morton Cc: Daniel Phillips , David Miller , riel@redhat.com, tgraf@suug.ch, linux-mm@kvack.org, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, Mike Christie In-Reply-To: <20060813215853.0ed0e973.akpm@osdl.org> References: <20060808211731.GR14627@postel.suug.ch> <44DBED4C.6040604@redhat.com> <44DFA225.1020508@google.com> <20060813.165540.56347790.davem@davemloft.net> <44DFD262.5060106@google.com> <20060813185309.928472f9.akpm@osdl.org> <1155530453.5696.98.camel@twins> <20060813215853.0ed0e973.akpm@osdl.org> Content-Type: text/plain Date: Mon, 14 Aug 2006 07:03:55 +0200 Message-Id: <1155531835.5696.103.camel@twins> Mime-Version: 1.0 X-Mailer: Evolution 2.7.91 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Sun, 2006-08-13 at 21:58 -0700, Andrew Morton wrote: > On Mon, 14 Aug 2006 06:40:53 +0200 > Peter Zijlstra wrote: > > > Testcase: > > > > Mount an NBD device as sole swap device and mmap > physical RAM, then > > loop through touching pages only once. > > Fix: don't try to swap over the network. Yes, there may be some scenarios > where people have no local storage, but it's reasonable to expect anyone > who is using Linux as an "enterprise storage platform" to stick a local > disk on the thing for swap. I wish you were right, however there seems to be a large demand to go diskless and swap over iSCSI because disks seem to be the nr. 1 failing piece of hardware in systems these days. > That leaves MAP_SHARED, but mm-tracking-shared-dirty-pages.patch will fix > that, will it not? Will makes it less likely. One can still have memory pressure, the remaining bits of memory can still get stuck in socket queues for blocked processes. From mboxrd@z Thu Jan 1 00:00:00 1970 Subject: Re: [RFC][PATCH 2/9] deadlock prevention core From: Peter Zijlstra In-Reply-To: <20060813215853.0ed0e973.akpm@osdl.org> References: <20060808211731.GR14627@postel.suug.ch> <44DBED4C.6040604@redhat.com> <44DFA225.1020508@google.com> <20060813.165540.56347790.davem@davemloft.net> <44DFD262.5060106@google.com> <20060813185309.928472f9.akpm@osdl.org> <1155530453.5696.98.camel@twins> <20060813215853.0ed0e973.akpm@osdl.org> Content-Type: text/plain Date: Mon, 14 Aug 2006 07:03:55 +0200 Message-Id: <1155531835.5696.103.camel@twins> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org Return-Path: To: Andrew Morton Cc: Daniel Phillips , David Miller , riel@redhat.com, tgraf@suug.ch, linux-mm@kvack.org, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, Mike Christie List-ID: On Sun, 2006-08-13 at 21:58 -0700, Andrew Morton wrote: > On Mon, 14 Aug 2006 06:40:53 +0200 > Peter Zijlstra wrote: > > > Testcase: > > > > Mount an NBD device as sole swap device and mmap > physical RAM, then > > loop through touching pages only once. > > Fix: don't try to swap over the network. Yes, there may be some scenarios > where people have no local storage, but it's reasonable to expect anyone > who is using Linux as an "enterprise storage platform" to stick a local > disk on the thing for swap. I wish you were right, however there seems to be a large demand to go diskless and swap over iSCSI because disks seem to be the nr. 1 failing piece of hardware in systems these days. > That leaves MAP_SHARED, but mm-tracking-shared-dirty-pages.patch will fix > that, will it not? Will makes it less likely. One can still have memory pressure, the remaining bits of memory can still get stuck in socket queues for blocked processes. -- 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