From owner-freebsd-stable@FreeBSD.ORG Fri Aug 21 03:21:00 2009 Return-Path: Delivered-To: freebsd-stable@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id A296210656C9 for ; Fri, 21 Aug 2009 03:21:00 +0000 (UTC) (envelope-from cmdlnkid@gmail.com) Received: from mail-yw0-f199.google.com (mail-yw0-f199.google.com [209.85.211.199]) by mx1.freebsd.org (Postfix) with ESMTP id 5104A8FC57 for ; Fri, 21 Aug 2009 03:21:00 +0000 (UTC) Received: by ywh37 with SMTP id 37so579278ywh.28 for ; Thu, 20 Aug 2009 20:20:59 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:received:received:date:from:to:cc:subject :in-reply-to:message-id:references:user-agent:x-openpgp-key-id :x-openpgp-key-fingerprint:mime-version:content-type; bh=HXainx2M4RXgnQmiTH1PKr0f8Jf0MNUnNo7WMupHvGI=; b=lkP7fJMWhkPt+0UaADtuM/pctoTMzAmKx1QD59hRbTfjD8DLkuLFmuY2eARuiYd8x+ qxR/krxLziX2g6GJS0mvjs7vwyHiytgyv47v30p3oUuYzvC9cBmUomvtvJtqgCddNlFi fgDi11+AZmCRHu1Obj9FDxF/DH/XojN1BFH14= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=date:from:to:cc:subject:in-reply-to:message-id:references :user-agent:x-openpgp-key-id:x-openpgp-key-fingerprint:mime-version :content-type; b=YOl0CatotuiNXNWSPrWlhXr5LXgT9q/cIvm6hwwkjxmC+r7Bm6+wgfg3bekHt1dBYX TlG9nm+yW2bmscYhbjmHsawty4U+fOyQaroktkJVECNOmgHYR76mI76ylz6UA/erjLSj ffBpBhiG6T/BvyUsr4YRyPg9O8nRSngj/lSy0= Received: by 10.91.161.34 with SMTP id n34mr503703ago.78.1250824859800; Thu, 20 Aug 2009 20:20:59 -0700 (PDT) Received: from firewall.5p.local (adsl-99-19-46-123.dsl.klmzmi.sbcglobal.net [99.19.46.123]) by mx.google.com with ESMTPS id 21sm1473618agb.65.2009.08.20.20.20.58 (version=TLSv1/SSLv3 cipher=RC4-MD5); Thu, 20 Aug 2009 20:20:58 -0700 (PDT) Date: Thu, 20 Aug 2009 23:20:44 -0400 From: CmdLnKid To: Daniel O'Connor In-Reply-To: <200908202212.22831.doconnor@gsoft.com.au> Message-ID: References: <200908201204.24914.doconnor@gsoft.com.au> <20090820114807.GQ9623@deviant.kiev.zoral.com.ua> <200908202212.22831.doconnor@gsoft.com.au> User-Agent: Alpine 2.00 (BSF 1167 2008-08-23) X-OpenPGP-Key-ID: 0xDFFDD218 X-OpenPGP-Key-Fingerprint: 2924 1C72 A6C2 852A 2094 25EE 9968 2636 DFFD D218 MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII; format=flowed Cc: Kostik Belousov , FreeBSD Stable Subject: Re: Blocked process 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: Fri, 21 Aug 2009 03:21:00 -0000 On Thu, 20 Aug 2009 08:42 -0000, doconnor wrote: > On Thu, 20 Aug 2009, Kostik Belousov wrote: >>> Things like ls on the console might take several seconds to respond >>> when the box didn't seem to be very busy (but wasn't idle, maybe >>> serving a little NFS). It wasn't the shell getting swapped out or >>> anything else obvious. This was on SMP, not using X. The problem >>> went away with 6.4R (had to stay with 6.x for unrelated reasons). >> >> 6.1 was released with a bug in NFS server, causing serious slowdown >> when non-MPSAFE fs was exported. > > Hmmm.. this is 6.2 (and a half) so I guess that's not my problem. > > Next! ;) > I had a problem like this once when the NFS mount stopped responding and any command that was issued seemed to hang. This all was happening while not paying attention to the NFS mount and that mount being various directories under /var and including /var/mail. A little deeper I eventually came across and what made me feel pretty stupid is that the "$SHELL" whether it be csh, ksh, bash or sh checks for mail on command completion or invocation and being so that the NFS mount stopped responding the process would hang until the mount came back or the machine was rebooted. I continued for a while using /var/mail over NFS while setting or unset mail variables for the shell. You may also want to check into whether something is trying to acquire a lock on a file over that NFS mount which could accrue some extra time making it seem like a process is hung. -- - (2^(N-1))