From owner-freebsd-questions@FreeBSD.ORG Thu Nov 6 11:27:46 2003 Return-Path: Delivered-To: freebsd-questions@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 6CFFB16A4CF for ; Thu, 6 Nov 2003 11:27:46 -0800 (PST) Received: from mail-relay1.mirrorimage.net (mail-relay1.mirrorimage.net [209.58.140.11]) by mx1.FreeBSD.org (Postfix) with ESMTP id 2BCB443FF5 for ; Thu, 6 Nov 2003 11:27:45 -0800 (PST) (envelope-from leblanc@mirrorimage.net) Received: from leblanc.mirrorimage.net (leblanc.mirrorimage.net [209.192.210.146]) by mail-relay1.mirrorimage.net (8.9.3/8.9.3) with ESMTP id OAA06446 for ; Thu, 6 Nov 2003 14:27:31 -0500 Received: from leblanc.mirrorimage.net (localhost [127.0.0.1]) hA6JRkMG006505 for ; Thu, 6 Nov 2003 14:27:46 -0500 (EST) (envelope-from leblanc@leblanc.mirrorimage.net) Received: (from leblanc@localhost) by leblanc.mirrorimage.net (8.12.8p1/8.12.8/Submit) id hA6JRksl006504 for freebsd-questions@FreeBSD.org; Thu, 6 Nov 2003 14:27:46 -0500 (EST) Date: Thu, 6 Nov 2003 14:27:46 -0500 From: Louis LeBlanc To: FreeBSD Questions Message-ID: <20031106192745.GJ5053@keyslapper.org> Mail-Followup-To: FreeBSD Questions Mime-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit User-Agent: Mutt/1.5.4i Subject: vfs.aio tuning question X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list Reply-To: freebsd-questions@FreeBSD.org List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 06 Nov 2003 19:27:46 -0000 Couldn't find any real explanation of these parameters online, but I noticed they appear to have disappeared in 4.8. I have a 4.6 system that shows the following parameters when sysctl -a is executed: vfs.aio.max_aio_per_proc: 72 vfs.aio.max_aio_queue_per_proc: 1024 vfs.aio.max_aio_procs: 32 vfs.aio.num_aio_procs: 0 vfs.aio.num_queue_count: 0 vfs.aio.max_aio_queue: 1024 vfs.aio.target_aio_procs: 4 vfs.aio.max_buf_aio: 72 vfs.aio.num_buf_aio: 0 vfs.aio.aiod_lifetime: 3000 vfs.aio.aiod_timeout: 1000 Now, I'm pretty sure these have something to do with asynchronous I/O, and I'm under the impression this is a bad thing to use. It appears this 4.6.2-RELEASE system is using it, but I don't know how to verify it or how to be sure it's not going to wreck something. If possible, I'd like someone to point me to a reference that describes the async features in some detail and particularly these parameters. Also, are they really gone from 4.8 or do they have to be 'turned on' somehow - and when is this an acceptable configuration? Thanks a lot folks. Lou -- Louis LeBlanc leblanc@keyslapper.org Fully Funded Hobbyist, KeySlapper Extrordinaire :) http://www.keyslapper.org ԿԬ All Finagle Laws may be bypassed by learning the simple art of doing without thinking.