Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760664AbZCXNVv (ORCPT ); Tue, 24 Mar 2009 09:21:51 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1760275AbZCXNVi (ORCPT ); Tue, 24 Mar 2009 09:21:38 -0400 Received: from dgate10.fujitsu-siemens.com ([80.70.172.49]:10588 "EHLO dgate10.fujitsu-siemens.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759745AbZCXNVh (ORCPT ); Tue, 24 Mar 2009 09:21:37 -0400 DomainKey-Signature: s=s768; d=fujitsu-siemens.com; c=nofws; q=dns; h=X-SBRSScore:X-IronPort-AV:Received:X-IronPort-AV: Received:Received:Message-ID:Date:From:Organization: User-Agent:MIME-Version:To:CC:Subject:References: In-Reply-To:X-Enigmail-Version:Content-Type: Content-Transfer-Encoding; b=QNBtXQnZd/1zp/pj2tZqmaV92FFKVNclLh2Aj5PlDXumf8XAPiJV531f 7hYCQGY3AbJHTt6BQOJw9M+oku3bczBuSocAkxda+SHIXAL7VzIxDFMbH AwDbZ99GvwljrFY; X-SBRSScore: None X-IronPort-AV: E=Sophos;i="4.38,412,1233529200"; d="scan'208";a="64815723" X-IronPort-AV: E=Sophos;i="4.38,412,1233529200"; d="scan'208";a="45481070" Message-ID: <49C8DE5C.9050705@fujitsu-siemens.com> Date: Tue, 24 Mar 2009 14:21:32 +0100 From: Martin Wilck Organization: Fujitsu Siemens Computers User-Agent: Thunderbird 2.0.0.15pre (X11/20080508) MIME-Version: 1.0 To: Corey Minyard CC: Greg KH , "openipmi-developer@lists.sourceforge.net" , "linux-kernel@vger.kernel.org" Subject: Re: [Openipmi-developer] Improving IPMI performance under load References: <49C27281.4040207@fujitsu-siemens.com> <49C2B994.7040808@acm.org> <20090319235114.GA18182@kroah.com> <49C3B6A5.5030408@acm.org> <20090320174701.GA14823@kroah.com> <49C3E03E.10506@acm.org> <49C78BE0.9090107@fujitsu-siemens.com> <49C7F368.5040304@acm.org> <49C8A823.6020809@fujitsu-siemens.com> <49C8DB54.4010200@acm.org> In-Reply-To: <49C8DB54.4010200@acm.org> X-Enigmail-Version: 0.95.6 Content-Type: text/plain; charset=ISO-8859-15; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1572 Lines: 45 Corey Minyard wrote: > I would guess that changing the nice value is the main thing that caused > the difference. The other changes probably didn't make as big a difference. That's true, but setting the nice level to 0 isn't "nice" without kipmid_max_busy. The two parameters help to make sure that kipmid doesn't use excessive CPU time. I am not sure about your reasons to call schedule() in every loop iteration. If there is no other process that needs to run, it will just waste cycles trying to figure that out. If there are other processes, you say yourself that "kipmid would never be scheduled in a busy system". Does it really make sense to call schedule() every microsecond? That's what kipmid effectively does if it waits for the KCS interface, because it'll do a port_inb() in every iteration which takes ca. 1us. > I'm ok with tuning like this, but most users are probably not going to > want this type of behavior. Let's wait and see :-) Martin -- Martin Wilck PRIMERGY System Software Engineer FSC IP ESP DEV 6 Fujitsu Siemens Computers GmbH Heinz-Nixdorf-Ring 1 33106 Paderborn Germany Tel: ++49 5251 525 2796 Fax: ++49 5251 525 2820 Email: mailto:martin.wilck@fujitsu-siemens.com Internet: http://www.fujitsu-siemens.com Company Details: http://www.fujitsu-siemens.com/imprint.html -- 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/