Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759115AbZASJtO (ORCPT ); Mon, 19 Jan 2009 04:49:14 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1756573AbZASJsz (ORCPT ); Mon, 19 Jan 2009 04:48:55 -0500 Received: from fg-out-1718.google.com ([72.14.220.158]:18340 "EHLO fg-out-1718.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753852AbZASJsy (ORCPT ); Mon, 19 Jan 2009 04:48:54 -0500 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=message-id:date:from:sender:to:subject:cc:in-reply-to:mime-version :content-type:content-transfer-encoding:content-disposition :references:x-google-sender-auth; b=uEQW0imTvf8pWp8rxU7ZVqyzVVxne43QwpZnKQ08UHDO3pXrJXyPkCrapWVzjf1hpU +b9W2Kf4Uwde03GmcfkBvZgsSlS1C8R6Xx6kznhxCyQ53WFbU9bYE+DIc+mfwvc7s0AG dvvuNwkOtPkxi6USwj4rDBJpNDdBGrgC4c05g= Message-ID: <84144f020901190148r7ea135b6uead33842e93e59c2@mail.gmail.com> Date: Mon, 19 Jan 2009 11:48:52 +0200 From: "Pekka Enberg" To: "Nick Piggin" Subject: Re: Mainline kernel OLTP performance update Cc: "Matthew Wilcox" , "Andrew Morton" , "Wilcox, Matthew R" , chinang.ma@intel.com, linux-kernel@vger.kernel.org, sharad.c.tripathi@intel.com, arjan@linux.intel.com, andi.kleen@intel.com, suresh.b.siddha@intel.com, harita.chilukuri@intel.com, douglas.w.styner@intel.com, peter.xihong.wang@intel.com, hubert.nueckel@intel.com, chris.mason@oracle.com, srostedt@redhat.com, linux-scsi@vger.kernel.org, "Andrew Vasquez" , "Anirban Chakraborty" , "Christoph Lameter" In-Reply-To: <200901191933.29322.nickpiggin@yahoo.com.au> MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Content-Disposition: inline References: <200901191813.07960.nickpiggin@yahoo.com.au> <1232352303.30141.25.camel@penberg-laptop> <200901191933.29322.nickpiggin@yahoo.com.au> X-Google-Sender-Auth: a2bd3eb568cbb62e Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1192 Lines: 25 Hi Nick, On Mon, Jan 19, 2009 at 10:33 AM, Nick Piggin wrote: >> All I am saying is that I don't like how we're fixing a performance bug >> with a shiny new allocator without a credible explanation why the >> current approach is not fixable. > > To be honest, my biggest concern with SLUB is the higher order pages > thing. But Christoph always poo poos me when I raise that concern, and > it's hard to get concrete numbers showing real fragmentation problems > when it can take days or months to start biting. To be fair to SLUB, we do have the pending slab defragmentation patches in my tree. Not that we have any numbers on if defragmentation helps and how much. IIRC, Christoph said one of the reasons for avoiding queues in SLUB is to be able to do defragmentation. But I suppose with SLQB we can do the same thing as long as we flush the queues before attempting to defrag. Pekka -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/