From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934331AbXC2Tbl (ORCPT ); Thu, 29 Mar 2007 15:31:41 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S934333AbXC2Tbl (ORCPT ); Thu, 29 Mar 2007 15:31:41 -0400 Received: from ug-out-1314.google.com ([66.249.92.173]:45135 "EHLO ug-out-1314.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934331AbXC2Tbk (ORCPT ); Thu, 29 Mar 2007 15:31:40 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=beta; h=received: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=oE8Hs6hujXgQbJhmsXOb1V4V6ZoT4Dt1OFUVZKgHLBImxNeyJmVr7RtU4oH6ARnPbesSHFhe3r+0HLyJd49i5esDxkUsrGY9LNIjo7JjQ/YPF1l3gP83j6kxRB/DldzMgoqfhvrtGApXacPaBJ23gAiA1PheXfcrxkg/jvihYOE= Message-ID: <75b66ecd0703291231n1b7cbcfcpbb16f4cfee933c2c@mail.gmail.com> Date: Thu, 29 Mar 2007 15:31:35 -0400 From: "Lee Revell" To: "Kevin Perros" Subject: Re: 2.6.20.3-rt8 - DMA suffers excessive delay periodically Cc: John , linux-kernel@vger.kernel.org In-Reply-To: <460C094C.8070304@free.fr> MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Content-Disposition: inline References: <46094728.40300@free.fr> <75b66ecd0703271341x34463c49w64bdac21a9741355@mail.gmail.com> <460A297A.2030200@free.fr> <460C094C.8070304@free.fr> X-Google-Sender-Auth: 2ce02bd4ce889309 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On 3/29/07, Kevin Perros wrote: > > No it is an "indutrial" motherboard. > > Although I don't know what makes it "industrial". > > > > Regards. > > > > Is this related to SMM? > > > > As far as I can tell, the BIOS is Phoenix AwardBIOS v6.00PG. > > > > Would someone know how to disable SMM in this BIOS? > > Usually you cannot disable SMM via the BIOS. You have to write chipset > specific Kernel code for that. The problem could also be something other than SMM, like DMA starvation by a video or disk controller. Try disabling all hard drive controllers and booting from a CD or USB stick. Also, try tweaking the expire_centisecs and writeback_centisecs values in /proc/sys/vm and see if it changes the period of the glitches. Lee