From owner-freebsd-performance@FreeBSD.ORG Fri Feb 1 05:06:49 2008 Return-Path: Delivered-To: freebsd-performance@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 2AB1A16B72B for ; Fri, 1 Feb 2008 05:06:49 +0000 (UTC) (envelope-from anderson@freebsd.org) Received: from ns.trinitel.com (186.161.36.72.static.reverse.ltdomains.com [72.36.161.186]) by mx1.freebsd.org (Postfix) with ESMTP id BCB7413C4D1 for ; Fri, 1 Feb 2008 05:06:48 +0000 (UTC) (envelope-from anderson@freebsd.org) Received: from proton.local (r74-193-81-203.pfvlcmta01.grtntx.tl.dh.suddenlink.net [74.193.81.203]) (authenticated bits=0) by ns.trinitel.com (8.14.1/8.14.1) with ESMTP id m114saAY013489; Thu, 31 Jan 2008 22:54:36 -0600 (CST) (envelope-from anderson@freebsd.org) Message-ID: <47A2A606.9080702@freebsd.org> Date: Thu, 31 Jan 2008 22:54:30 -0600 From: Eric Anderson User-Agent: Thunderbird 2.0.0.9 (Macintosh/20071031) MIME-Version: 1.0 To: Dieter References: <200801310147.BAA04522@sopwith.solgatos.com> In-Reply-To: <200801310147.BAA04522@sopwith.solgatos.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-Spam-Status: No, score=-2.1 required=5.0 tests=AWL,BAYES_00 autolearn=ham version=3.1.8 X-Spam-Checker-Version: SpamAssassin 3.1.8 (2007-02-13) on ns.trinitel.com Cc: freebsd-performance@freebsd.org, Steven Hartland Subject: Re: newfs locks entire machine for 20seconds X-BeenThere: freebsd-performance@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Performance/tuning List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 01 Feb 2008 05:06:49 -0000 Dieter wrote: >>> What *exactly* do you mean by >>> >>>> machine still locks up with no activity for anywhere from 20 to 30 seconds. >>> Is there disk activity? (e.g. activity light(s) flashing if you have them) >> Cant tell if there is disk activity its in a DC miles away ;) >> >>> Does top continue to update the screen during the 20-30 seconds? >>> >>> I'm thinking that newfs has queued up a bunch of disk i/o, and other >>> disk i/o gets locked out, but activities that don't require any disk i/o >>> (like top, once it is up and running) could continue. Is that what is >>> happening? >> No all sessions totally freeze. I have top set to 1 second refreshes and >> the clock literally stops and then 20-30 seconds later continues. > > Wow! > >> All sessions are via ssh not X if that's of interest. >> >> I could understand if IO to disk for other processes became slow but >> everything including things like top just stop which is quite odd and >> concerning. > > Ok, new idea. Your disk activity is via the network, and your sessions > are via the network. Could it be that something network related is saturated? I saw this once before, a long time back, and every time I went through a debugging session, it came to some kind of lock on the sysctl tree with regards to the geom info (maybe the XML kind of tree dump or something). I don't recall all the details, but it was something like that. Eric