From mboxrd@z Thu Jan 1 00:00:00 1970 Message-ID: <43644C22.8050501@yahoo.com.au> Date: Sun, 30 Oct 2005 15:29:22 +1100 From: Nick Piggin MIME-Version: 1.0 Subject: Re: munmap extremely slow even with untouched mapping. References: <20051028013738.GA19727@attica.americas.sgi.com> <43620138.6060707@yahoo.com.au> In-Reply-To: Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org Return-Path: To: Hugh Dickins Cc: Robin Holt , linux-kernel@vger.kernel.org, linux-mm@kvack.org List-ID: Hugh Dickins wrote: > Yes, it's a good observation from Robin. > > It'll have been spoiling the exit speedup we expected from your > 2.6.14 copy_page_range "Don't copy [faultable] ptes" fork speedup. > Yep. Not to mention it is probably responsible for some of the 4 level page table performance slowdowns on x86-64. > > > I prefer your patch too. But I'm not very interested in temporary > speedups relative to 2.6.14. Attacking this is a job I'd put off > until after the page fault scalability changes, which make it much > easier to do a proper job. > Yeah definitely. I wonder if we should go with Robin's fix (+/- my variation) as a temporary measure for 2.6.15? -- 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