From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Wed, 12 Jan 2005 10:43:26 -0800 From: Andrew Morton Subject: Re: page table lock patch V15 [0/7]: overview Message-Id: <20050112104326.69b99298.akpm@osdl.org> In-Reply-To: References: <41E4BCBE.2010001@yahoo.com.au> <20050112014235.7095dcf4.akpm@osdl.org> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org Return-Path: To: Christoph Lameter Cc: nickpiggin@yahoo.com.au, torvalds@osdl.org, ak@muc.de, hugh@veritas.com, linux-mm@kvack.org, linux-ia64@vger.kernel.org, linux-kernel@vger.kernel.org, benh@kernel.crashing.org List-ID: Christoph Lameter wrote: > > > Do we have measurements of the negative and/or positive impact on smaller > > machines? > > Here is a measurement of 256M allocation on a 2 way SMP machine 2x > PIII-500Mhz: > > Gb Rep Threads User System Wall flt/cpu/s fault/wsec > 0 10 1 0.005s 0.016s 0.002s 54357.280 52261.895 > 0 10 2 0.008s 0.019s 0.002s 43112.368 42463.566 > > With patch: > > Gb Rep Threads User System Wall flt/cpu/s fault/wsec > 0 10 1 0.005s 0.016s 0.002s 54357.280 53439.357 > 0 10 2 0.008s 0.018s 0.002s 44650.831 44202.412 > > So only a very minor improvements for old machines (this one from ~ 98). OK. But have you written a test to demonstrate any performance regressions? From, say, the use of atomic ops on ptes? -- 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