From owner-freebsd-stable@FreeBSD.ORG Wed Jan 27 00:31:55 2010 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 45BE21065692 for ; Wed, 27 Jan 2010 00:31:55 +0000 (UTC) (envelope-from dgerow@afflictions.org) Received: from out2.smtp.messagingengine.com (out2.smtp.messagingengine.com [66.111.4.26]) by mx1.freebsd.org (Postfix) with ESMTP id 14C198FC14 for ; Wed, 27 Jan 2010 00:31:54 +0000 (UTC) Received: from compute1.internal (compute1.internal [10.202.2.41]) by gateway1.messagingengine.com (Postfix) with ESMTP id F1FEDCE57B for ; Tue, 26 Jan 2010 19:12:57 -0500 (EST) Received: from heartbeat1.messagingengine.com ([10.202.2.160]) by compute1.internal (MEProxy); Tue, 26 Jan 2010 19:12:58 -0500 DKIM-Signature: v=1; a=rsa-sha1; c=relaxed/relaxed; d=messagingengine.com; h=date:from:to:subject:message-id:references:mime-version:content-type:in-reply-to; s=smtpout; bh=8tzZ8NoKxi8ckXrOZu7nqUL5vgU=; b=EfC6yvC5ebWw0EYxhfOi8U4jWFo82ha6FRZZLCE6SOyX/r6cU1UlFsvqA+gHPb2tcwXZJ4LYAQm+e+jo6sKysdF2t1jt9Pwhx4WFSLgBEihImn6NfmjuZk9xnRRvHf9+9lXnEQla0h5nav306lFXN/FTR9JmVFtVYoR87kUShWA= X-Sasl-enc: pA39PXUy6ut6ztIZ0JstT4jXHFxraeEIhWVLjS70JFiz 1264551177 Received: from plebeian.afflictions.org (CPE000db917e8b9-CM0019475d4056.cpe.net.cable.rogers.com [174.115.162.77]) by mail.messagingengine.com (Postfix) with ESMTPSA id B9C0E49A915 for ; Tue, 26 Jan 2010 19:12:57 -0500 (EST) Received: by plebeian.afflictions.org (Postfix, from userid 1001) id 7348BD2; Tue, 26 Jan 2010 19:12:01 -0500 (EST) Date: Tue, 26 Jan 2010 19:12:01 -0500 From: Damian Gerow To: freebsd-stable@freebsd.org Message-ID: <20100127001201.GE9206@plebeian.afflictions.org> References: <20100126235458.GA12634@swelter.hanley.stade.co.uk> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20100126235458.GA12634@swelter.hanley.stade.co.uk> User-Agent: Mutt/1.5.20 (2009-06-14) Subject: Re: immense delayed write to file system (ZFS and UFS2), performance issues 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: Wed, 27 Jan 2010 00:31:55 -0000 Adrian Wontroba wrote: : How about using the "write every 5 seconds" python script posted earlier : in this thread by erik@tefre.com? Works nicely for me and stops the load : cycle count increase. I have a WD2003FYPS sitting in a system, to be used for testing. Bought it just before this thread started, and here's what it looks like right now: 9 Power_On_Hours 0x0032 100 100 000 Old_age Always - 508 193 Load_Cycle_Count 0x0032 200 200 000 Old_age Always - 2710 This drive is sitting, unused, with no filesystem, and I've performed approximately zero writes to the disk. Having a script kick off and write to a disk will help so long as that disk is writable; if it's being used as a hot spare in a raidz array, it's not going to help much.