From mboxrd@z Thu Jan 1 00:00:00 1970 Message-ID: <4366AFC7.3060505@yahoo.com.au> Date: Tue, 01 Nov 2005 10:59:03 +1100 From: Nick Piggin MIME-Version: 1.0 Subject: Re: [Lhms-devel] [PATCH 0/7] Fragmentation Avoidance V19 References: <20051030183354.22266.42795.sendpatchset@skynet.csn.ul.ie><20051031055725.GA3820@w-mikek2.ibm.com><4365BBC4.2090906@yahoo.com.au><20051030235440.6938a0e9.akpm@osdl.org><27700000.1130769270@[10.10.2.4]> <20051031112409.153e7048.akpm@osdl.org> <3660000.1130787652@flay> In-Reply-To: <3660000.1130787652@flay> Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org Return-Path: To: "Martin J. Bligh" Cc: Andrew Morton , kravetz@us.ibm.com, mel@csn.ul.ie, linux-mm@kvack.org, linux-kernel@vger.kernel.org, lhms-devel@lists.sourceforge.net List-ID: Martin J. Bligh wrote: > --On Monday, October 31, 2005 11:24:09 -0800 Andrew Morton wrote: >>I suspect this would all be a non-issue if the net drivers were using >>__GFP_NOWARN ;) > > > We still need to allocate them, even if it's GFP_KERNEL. As memory gets > larger and larger, and we have no targetted reclaim, we'll have to blow > away more and more stuff at random before we happen to get contiguous > free areas. Just statistics aren't in your favour ... Getting 4 contig > pages on a 1GB desktop is much harder than on a 128MB machine. > However, these allocations are not of the "easy to reclaim" type, in which case they just use the regular fragmented-to-shit areas. If no contiguous pages are available from there, then an easy-reclaim area needs to be stolen, right? In which case I don't see why these patches don't have similar long term failure cases if there is strong demand for higher order allocations. Prolong things a bit, perhaps, but... > Is not going to get better as time goes on ;-) Yeah, yeah, I know, you > want recreates, numbers, etc. Not the easiest thing to reproduce in a > short-term consistent manner though. > Regardless, I think we need to continue our steady move away from higher order allocation requirements. -- SUSE Labs, Novell Inc. Send instant messages to your online friends http://au.messenger.yahoo.com -- 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