From owner-freebsd-stable@FreeBSD.ORG Mon Jul 16 13:34:37 2012 Return-Path: Delivered-To: freebsd-stable@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [69.147.83.52]) by hub.freebsd.org (Postfix) with ESMTP id AC1E0106564A for ; Mon, 16 Jul 2012 13:34:37 +0000 (UTC) (envelope-from prvs=1544f5cf44=killing@multiplay.co.uk) Received: from mail1.multiplay.co.uk (mail1.multiplay.co.uk [85.236.96.23]) by mx1.freebsd.org (Postfix) with ESMTP id F14608FC0A for ; Mon, 16 Jul 2012 13:34:36 +0000 (UTC) X-Spam-Processed: mail1.multiplay.co.uk, Mon, 16 Jul 2012 14:34:30 +0100 X-Spam-Checker-Version: SpamAssassin 3.2.5 (2008-06-10) on mail1.multiplay.co.uk X-Spam-Level: X-Spam-Status: No, score=-5.0 required=6.0 tests=USER_IN_WHITELIST shortcircuit=ham autolearn=disabled version=3.2.5 Received: from r2d2 ([188.220.16.49]) by mail1.multiplay.co.uk (mail1.multiplay.co.uk [85.236.96.23]) (MDaemon PRO v10.0.4) with ESMTP id md50020796474.msg for ; Mon, 16 Jul 2012 14:34:28 +0100 X-MDRemoteIP: 188.220.16.49 X-Return-Path: prvs=1544f5cf44=killing@multiplay.co.uk X-Envelope-From: killing@multiplay.co.uk X-MDaemon-Deliver-To: freebsd-stable@freebsd.org Message-ID: <6BF15045231C4F399F10BBBEA66A2CF8@multiplay.co.uk> From: "Steven Hartland" To: , "Michael Ross" References: Date: Mon, 16 Jul 2012 14:34:30 +0100 MIME-Version: 1.0 Content-Type: text/plain; format=flowed; charset="iso-8859-15"; reply-type=response Content-Transfer-Encoding: 7bit X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2900.5931 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.6157 Cc: Subject: Re: 8.2 ->8.3 regression on disk writes X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 16 Jul 2012 13:34:37 -0000 ----- Original Message ----- From: "Michael Ross" To: Sent: Monday, July 16, 2012 2:23 PM Subject: 8.2 ->8.3 regression on disk writes > Hello, > > using 8.2 the machine runs fine, > using 8.3 or higher, not so much. > > In laymans terms, > if I do "too many" writes/time just once, the machine can't do any disk > access for a couple of hours. > > As in: What's already running stays running, no crashes or anything, > but as soon as I need to read from disk (login, start program not cached > in memory from previous run), > I'm all out of luck. > I killed the testing ftp-transfer about 15 seconds after the transfer > speed dropped, > now I'm waiting for 10+ minutes for ``top'' to start. > > > I can install ports and kernels and world fine, > but "ezjail-admin install" or transferring a few GB of files from another > machine sends it to limbo. > > The next step would likely be to go through the kernel changes between 8.2 > and 8.3 to narrow it down, > I'd appreciate pointers as to what kernel changes to look out for, > or other suggestions on what to do. > > Verbose dmesg: http://gurder.ross.cx/misc/dmesg.txt You have some strangeness there: I see: "real memory = 17179869184 (16384 MB)" "avail memory = 2050920448 (1955 MB)" So even though you have 16GB ram your only using 2GB of it which will likely cause slowness under ZFS including disabling prefetch "ZFS NOTICE: Prefetch is disabled by default if less than 4GB of RAM is present; to enable, add "vfs.zfs.prefetch_disable=0" to /boot/loader.conf." Is this a VM or something? Regards Steve ================================================ This e.mail is private and confidential between Multiplay (UK) Ltd. and the person or entity to whom it is addressed. In the event of misdirection, the recipient is prohibited from using, copying, printing or otherwise disseminating it or any information contained in it. In the event of misdirection, illegible or incomplete transmission please telephone +44 845 868 1337 or return the E.mail to postmaster@multiplay.co.uk.