From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from pigeon.gentoo.org ([69.77.167.62] helo=lists.gentoo.org) by finch.gentoo.org with esmtp (Exim 4.60) (envelope-from ) id 1Jw23k-0004sE-Ll for garchives@archives.gentoo.org; Tue, 13 May 2008 21:29:21 +0000 Received: from pigeon.gentoo.org (localhost [127.0.0.1]) by pigeon.gentoo.org (Postfix) with SMTP id B951EE0577; Tue, 13 May 2008 21:27:19 +0000 (UTC) Received: from iggypop2.siwnet.net (iggypop2.siwnet.net [81.216.65.12]) by pigeon.gentoo.org (Postfix) with ESMTP id 8BEF6E0577 for ; Tue, 13 May 2008 21:27:19 +0000 (UTC) Received: from localhost (unknown [127.0.0.1]) by iggypop2.siwnet.net (Postfix) with ESMTP id 750E73FF9D1 for ; Tue, 13 May 2008 23:27:18 +0200 (CEST) X-Virus-Scanned: amavisd-new at iggypop2.siwnet.net Received: from iggypop2.siwnet.net ([127.0.0.1]) by localhost (iggypop2.siwnet.net [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 243cjAM7TTgS for ; Tue, 13 May 2008 23:27:15 +0200 (CEST) Received: from [192.168.1.100] (71.57.227.87.static.th.siw.siwnet.net [87.227.57.71]) (Authenticated sender: peka@min-epost.net) by iggypop2.siwnet.net (Postfix) with ESMTP id A03903FF97C for ; Tue, 13 May 2008 23:27:15 +0200 (CEST) Message-ID: <482A07B2.5060604@coolmail.se> Date: Tue, 13 May 2008 23:27:14 +0200 From: pk User-Agent: Thunderbird 2.0.0.14 (X11/20080505) Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-Id: Gentoo Linux mail X-BeenThere: gentoo-user@lists.gentoo.org Reply-to: gentoo-user@lists.gentoo.org MIME-Version: 1.0 To: gentoo-user@lists.gentoo.org Subject: Re: [gentoo-user] [OT?] MTRR and PAT References: <4826A520.1030007@coolmail.se> <350fc7cf0805110057h228ca2ddja777b60cc8658d77@mail.gmail.com> <4826AB0E.3040805@coolmail.se> <350fc7cf0805111303p538365a6u306ba633ae92daf3@mail.gmail.com> <48288CE1.8020905@coolmail.se> <350fc7cf0805121153t74980c43vf6e551d4470d50b8@mail.gmail.com> In-Reply-To: <350fc7cf0805121153t74980c43vf6e551d4470d50b8@mail.gmail.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Archives-Salt: 8eabf848-2408-4f42-b779-332cae87830a X-Archives-Hash: c94df5058528b6d506fe66b9ca3c6f7e Andrey Falko wrote: > Ahh I see. I don't know much about MTRR...all I know is that you can > adjust them via grub: > http://www.gentoo.org/doc/en/handbook/handbook-x86.xml?part=1&chap=10 Hmm... I missed that one. Thanks. My grub kernel command line (which I haven't given much thought to since it's inception many years ago): root=/dev/sda2 vga=804 video=vesafb:1280x1024-32@85,mtrr:3,ywrap This should tell vesafb to set MTRR to use write-combining (for which memory region, I don't know), but it doesn't work for me, for some reason. All of my mem (under X) is set to write-back with the exception of 1Mb set to uncacheable. My other computer has even stranger settings and the kernel log complains about MTRR settings not correctly setup (it states that the BIOS probably doesn't init's both cores). > . You probably read this already: > http://en.wikipedia.org/wiki/Memory_Type_Range_Registers Yep. Here's a few more if you (or anyone else) find this interesting: http://en.wikipedia.org/wiki/Write-combining http://en.wikipedia.org/wiki/Cache Basically the MTRR (and PAT) determines how the processor (and it's cache(s)) accesses the memory regions (in the MTRR). Xorg supposedly should set up the MTRR when it starts. > Yeh, I have Nvidia cards, so I guess ATI is different. Perhaps. Thanks again! It's always good to weather one's thoughts on a subject... This just got me thinking. I'll investigate what the MTRR settings look like before the display manager starts... Best regards Peter K -- gentoo-user@lists.gentoo.org mailing list