From owner-freebsd-smp Fri Mar 22 0:15:59 2002 Delivered-To: freebsd-smp@freebsd.org Received: from harrier.prod.itd.earthlink.net (harrier.mail.pas.earthlink.net [207.217.120.12]) by hub.freebsd.org (Postfix) with ESMTP id 3F12737B41A for ; Fri, 22 Mar 2002 00:15:53 -0800 (PST) Received: from pool0061.cvx21-bradley.dialup.earthlink.net ([209.179.192.61] helo=mindspring.com) by harrier.prod.itd.earthlink.net with esmtp (Exim 3.33 #1) id 16oKDF-0007eZ-00; Fri, 22 Mar 2002 00:15:49 -0800 Message-ID: <3C9AE821.6A4B47ED@mindspring.com> Date: Fri, 22 Mar 2002 00:15:29 -0800 From: Terry Lambert X-Mailer: Mozilla 4.7 [en]C-CCK-MCD {Sony} (Win98; U) X-Accept-Language: en MIME-Version: 1.0 To: ?? Cc: freebsd-smp@FreeBSD.ORG Subject: Re: SMP Error in VIA 694 based bord References: <3C992BE9.169C1501@mindspring.com> <00b101c1d16c$ea162ec0$eb1148d3@chris> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: owner-freebsd-smp@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.org ?? wrote: > > thanks to Terry, I added option DISABLE_PSE,then the smp works fine,I > already boot over 30hrs,and running stable, thank > you for your help. > May I ask you? what is PSE,it seens like a cpu function? Thanks for posting to the list. People generally don't believe the FreeBSD has a PSE problem, without a confirming success report in the DISABLE_PSE case, like yours. Actually, Satoshi Asami and the people still at ClickArray should be able to conrim the problem as well as the workaround. It is the page size extension for the use of 4M pages. There is a subtle bug in both Intel and AMD processors with regard to the PSE. FreeBSD used to accidently work around it. Apparently, it no longer does. By disabling the PSE, you prevent the use of 4M pages, which avoids triggering the bug in the first place. If someone who cares about 4M pages wants to narrow down the code change that resulted in FreeBSD no longer working around the problem, it night be useful to seperate the use of the PSE for the kernel from the use of the PSE for memory mapped devices. -- Terry To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-smp" in the body of the message