From owner-freebsd-current@FreeBSD.ORG Thu Jul 15 00:34:04 2004 Return-Path: Delivered-To: freebsd-current@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 092A416A4EE for ; Thu, 15 Jul 2004 00:34:04 +0000 (GMT) Received: from duke.cs.duke.edu (duke.cs.duke.edu [152.3.140.1]) by mx1.FreeBSD.org (Postfix) with ESMTP id 8E12C43D1F for ; Thu, 15 Jul 2004 00:34:03 +0000 (GMT) (envelope-from gallatin@cs.duke.edu) Received: from grasshopper.cs.duke.edu (grasshopper.cs.duke.edu [152.3.145.30]) by duke.cs.duke.edu (8.12.10/8.12.10) with ESMTP id i6F0Y2Wg020189 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO); Wed, 14 Jul 2004 20:34:02 -0400 (EDT) Received: (from gallatin@localhost) by grasshopper.cs.duke.edu (8.12.9p2/8.12.9/Submit) id i6F0Xtxj033019; Wed, 14 Jul 2004 20:33:55 -0400 (EDT) (envelope-from gallatin) From: Andrew Gallatin MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Message-ID: <16629.53491.242495.5678@grasshopper.cs.duke.edu> Date: Wed, 14 Jul 2004 20:33:55 -0400 (EDT) To: Doug White In-Reply-To: <20040713184408.W527@carver.gumbysoft.com> References: <6.1.2.0.2.20040712142407.02d38a98@64.124.166.215> <20040713184408.W527@carver.gumbysoft.com> X-Mailer: VM 6.75 under 21.1 (patch 12) "Channel Islands" XEmacs Lucid cc: freebsd-current@freebsd.org cc: Gary Stanley Subject: Re: Network related procs hang in unusual sfpbsy state X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 15 Jul 2004 00:34:04 -0000 Doug White writes: > On Mon, 12 Jul 2004, Gary Stanley wrote: > > > New current kernel from about 3 days ago, certain processes hang after > > about a day in this state; > > > > 80 599 1 0 -16 -2 59020 53548 sfpbsy D< ?? 1141:08.65 > > /mnt/zeus/web/bin/zeus.web > > sfpbsy is used in do_sendfile(). It blocks on this if a page for the file > its trying to send is busy. It may be blocked on another process or the > volume its on is taking a while to page the page in. You might check the > logs or whatever for zeus and see if all of them are hung trying to > request the same file, or if its on the same filesystem. > > Anyone who understands the reason things get marked PG_BUSY can chime in > here :) It basically means "don't touch this page" and is set when the page is being changed. Eg, when vm_fault() is working with a page, or when vm_page_alloc() is allocating one. Sendfile sleeps with also_m_busy=TRUE, which means that it could be waiting for an io to complete and cause m->busy to drop to zero. (vm_page_io_finish()). Drew