From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Thu, 29 Jul 2004 09:54:33 -0500 From: Brent Casavant Reply-To: Brent Casavant Subject: Re: Scaling problem with shmem_sb_info->stat_lock In-Reply-To: <20040728235343.GG2334@holomorphy.com> Message-ID: References: <20040728022625.249c78da.akpm@osdl.org> <20040728095925.GQ2334@holomorphy.com> <20040728235343.GG2334@holomorphy.com> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-linux-mm@kvack.org Return-Path: To: William Lee Irwin III Cc: Andrew Morton , Hugh Dickins , linux-mm@kvack.org List-ID: On Wed, 28 Jul 2004, William Lee Irwin III wrote: > On Wed, Jul 28, 2004 at 05:21:58PM -0500, Brent Casavant wrote: > > The "obvious" fix is to morph the code so that the swap entries can be > > updated in parallel to eachother and in parallel to the other miscellaneous > > fields in the shmem_inode_info structure. But this would be one *nasty* > > piece of work to accomplish, much less accomplish cleanly and correctly. > > I'm pretty sure my Linux skillset isn't up to the task, though it hasn't > > kept me from trying. On the upside I don't think it would significantly > > impact performance on low processor-count systems, if we can manage to > > do it at all. > > I'm kind of hoping for a fairy godmother to drop in, wave her magic wand, > > and say "Here's the quick and easy and obviously correct solution". But > > what're the chances of that :). > > This may actually have some positive impact on highly kernel-intensive > low processor count database workloads (where kernel intensiveness makes > up for the reduced processor count vs. the usual numerical applications > at high processor counts on SGI systems). Good to know. It always amazes me how close my knowledge horizon really is. > At the moment a number of > stability issues have piled up that I need to take care of, but I would > be happy to work with you on devising methods of addressing this when > those clear up, which should be by the end of this week. Count me in. I've been chewing on this one for a while now, and I'll be more than happy to help. Brent -- Brent Casavant bcasavan@sgi.com Forget bright-eyed and Operating System Engineer http://www.sgi.com/ bushy-tailed; I'm red- Silicon Graphics, Inc. 44.8562N 93.1355W 860F eyed and bushy-haired. -- 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: aart@kvack.org