From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Mon, 9 Apr 2007 11:50:21 -0700 (PDT) From: Christoph Lameter Subject: Re: [QUICKLIST 1/4] Quicklists for page table pages V5 In-Reply-To: <20070409114827.d3cbf705.akpm@linux-foundation.org> Message-ID: References: <20070409182509.8559.33823.sendpatchset@schroedinger.engr.sgi.com> <20070409114827.d3cbf705.akpm@linux-foundation.org> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-linux-mm@kvack.org Return-Path: To: Andrew Morton Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, ak@suse.de List-ID: On Mon, 9 Apr 2007, Andrew Morton wrote: > On Mon, 9 Apr 2007 11:25:09 -0700 (PDT) > Christoph Lameter wrote: > > > On x86_64 this cuts allocation overhead for page table pages down to > > a fraction (kernel compile / editing load. TSC based measurement > > of times spend in each function): > > > > no quicklist > > > > pte_alloc 1569048 4.3s(401ns/2.7us/179.7us) > > pmd_alloc 780988 2.1s(337ns/2.7us/86.1us) > > pud_alloc 780072 2.2s(424ns/2.8us/300.6us) > > pgd_alloc 260022 1s(920ns/4us/263.1us) > > > > quicklist: > > > > pte_alloc 452436 573.4ms(8ns/1.3us/121.1us) > > pmd_alloc 196204 174.5ms(7ns/889ns/46.1us) > > pud_alloc 195688 172.4ms(7ns/881ns/151.3us) > > pgd_alloc 65228 9.8ms(8ns/150ns/6.1us) > > > > pgd allocations are the most complex and there we see the most dramatic > > improvement (may be we can cut down the amount of pgds cached somewhat?). > > But even the pte allocations still see a doubling of performance. > > Was there any observeable change in overall runtime? The kernel compile times fluctuates as usual. There was a tendency for the times to be less but no clear win as discussed before. > What are the numbers in parentheses? (minimum/average/maximum) -- 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