Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S263213AbUCTDww (ORCPT ); Fri, 19 Mar 2004 22:52:52 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S263221AbUCTDww (ORCPT ); Fri, 19 Mar 2004 22:52:52 -0500 Received: from mail-05.iinet.net.au ([203.59.3.37]:64976 "HELO mail.iinet.net.au") by vger.kernel.org with SMTP id S263213AbUCTDwu (ORCPT ); Fri, 19 Mar 2004 22:52:50 -0500 Message-ID: <405BC003.6080507@cyberone.com.au> Date: Sat, 20 Mar 2004 14:52:35 +1100 From: Nick Piggin User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.6) Gecko/20040122 Debian/1.6-1 X-Accept-Language: en MIME-Version: 1.0 To: Mark Wong CC: Andrew Morton , axboe@suse.de, linux-kernel@vger.kernel.org Subject: Re: 2.6.4-mm2 References: <20040314172809.31bd72f7.akpm@osdl.org> <200403181737.i2IHbCE09261@mail.osdl.org> <20040318100615.7f2943ea.akpm@osdl.org> <20040318192707.GV22234@suse.de> <20040318191530.34e04cb2.akpm@osdl.org> <20040318194150.4de65049.akpm@osdl.org> <20040319183906.I8594@osdlab.pdx.osdl.net> <20040319185026.56db3bf7.akpm@osdl.org> <20040319185345.A4610@osdlab.pdx.osdl.net> In-Reply-To: <20040319185345.A4610@osdlab.pdx.osdl.net> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2159 Lines: 61 Mark Wong wrote: >On Fri, Mar 19, 2004 at 06:50:26PM -0800, Andrew Morton wrote: > >>Mark Wong wrote: >> >>>On Thu, Mar 18, 2004 at 07:41:50PM -0800, Andrew Morton wrote: >>> >>>>Andrew Morton wrote: >>>> >>>>>Mark, if it's OK I'll run up some kernels for you to test. >>>>> >>>>At >>>> >>>> http://www.zip.com.au/~akpm/linux/patches/markw/ >>>> >>>Ok, looks like I take the first hit with the 02 patch. Here's re-summary: >>> >>>kernel 16 kb 32 kb 64 kb 128 kb 256 kb 512 kb >>>2.6.3 2308 2335 2348 2334 >>>2.6.4-mm2 2028 2048 2074 2096 2082 2078 >>>2.6.5-rc1-01 2394 >>>2.6.5-rc1-02 2117 >>>2.6.5-rc1-mm2 2036 >>> >>Thanks, so it's the CPU scheduler changes. Is that machine hyperthreaded? >>And do you have CONFIG_X86_HT enabled? >> > >Yes and CONFIG_X86_HT is enabled but I have hyperthreading disabled with >'acpi=off noht' (whichever one does it.) > The oprofile for the 01 kernel says CPU: P4 / Xeon, speed 1497.76 MHz (estimated) while the 02 kernel says CPU: P4 / Xeon with 2 hyper-threads, speed 1497.57 MHz (estimated) What's going on there? Other than that, nothing in the kernel profile jumps out at me: schedule, __copy_from_user_ll and __copy_to_user_ll are all significantly lower *after* the CPU scheduler changes, which is an indicator that cache behaviour is better. Sar says average context switches/second were 9064 and 6567 before and after. The only thing I can see is the CPU utilisation averages show the scheduler patches have more of a tendancy to load up one CPU more before moving to another. This actually should be good behaviour, generally but I wonder if it is hurting at all. I would be really surprised if it was that significant. - 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/