From mboxrd@z Thu Jan 1 00:00:00 1970 Message-ID: <44505FA6.70508@yahoo.com.au> Date: Thu, 27 Apr 2006 16:07:34 +1000 From: Nick Piggin MIME-Version: 1.0 Subject: Re: Lockless page cache test results References: <4t153d$r2dpi@azsmga001.ch.intel.com> In-Reply-To: <4t153d$r2dpi@azsmga001.ch.intel.com> Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org Return-Path: To: "Chen, Kenneth W" Cc: 'Jens Axboe' , linux-kernel@vger.kernel.org, 'Nick Piggin' , 'Andrew Morton' , linux-mm@kvack.org List-ID: Chen, Kenneth W wrote: > Jens Axboe wrote on Wednesday, April 26, 2006 12:46 PM > >>>It's interesting, single threaded performance is down a little. Is >>>this significant? In some other results you showed me with 3 splices >>>each running on their own file (ie. no tree_lock contention), lockless >>>looked slightly faster on the same machine. >> >>I can do the same numbers on a 2-way em64t for comparison, that should >>get us a little better coverage. > > > > I throw the lockless patch and Jens splice-bench into our benchmark harness, > here are the numbers I collected, on the following hardware: > > (1) 2P Intel Xeon, 3.4 GHz/HT, 2M L2 > (2) 4P Intel Xeon, 3.0 GHz/HT, 8M L3 > (3) 4P Intel Xeon, 3.0 GHz/DC/HT, 2M L2 (per core) > > Here are the graph: Thanks a lot Ken. So pagecache lookup performance goes up about 15-25% in single threaded tests on your P4s. Phew, I wasn't dreaming it. It is a pity that ipf hasn't improved similarly (and even slowed down a bit, if Jens' numbers are significant to that range). Next time I spend some cycles on lockless pagecache, I'll try to scrounge an ipf and see if I can't improve it (I don't expect miracles). Thanks, Nick -- 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