From owner-freebsd-stable@FreeBSD.ORG Wed Jan 27 00:45:28 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 B5E06106566C for ; Wed, 27 Jan 2010 00:45:28 +0000 (UTC) (envelope-from dan.naumov@gmail.com) Received: from mail-yw0-f197.google.com (mail-yw0-f197.google.com [209.85.211.197]) by mx1.freebsd.org (Postfix) with ESMTP id 68C348FC08 for ; Wed, 27 Jan 2010 00:45:28 +0000 (UTC) Received: by ywh35 with SMTP id 35so4162224ywh.7 for ; Tue, 26 Jan 2010 16:45:27 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:mime-version:received:date:message-id:subject :from:to:content-type; bh=cvDMmLkPGPPhG9SsfnZs95mQBCtkL2NbRgAxARYxTQQ=; b=iNMxSPeErZIsBmIehfIh06LwA2x1KjiN6QSUsqtOW2RruPtAWZ9X0zZlP8rxdvdFRZ Ne2A1BDHKgXKbgUl/s57mnXVq4onsNv8Sg0g9t67dLxmrEYbAaH/L8xkUjfswq73iM3V p8RQNlw+DnFk6Cxw7JpYgBmHKM9pZdn9O8oKE= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:date:message-id:subject:from:to:content-type; b=SVqMGCiIwsjGRqU1DvVuA/SebQJII0xYnUP4RkLu95gZZvmL1HMPN5RAHyZcoGcMEU 28SPKH/PhOEN4Rw53iseBzN2AEcvyHDaKedLXpTOYJkOHOy7J+ICzUb8rlSXgin8BQYx hw29+1NKNiXgeV0l7asYBQCY9xmx7VfMdpg9M= MIME-Version: 1.0 Received: by 10.101.2.13 with SMTP id e13mr9605383ani.195.1264553127674; Tue, 26 Jan 2010 16:45:27 -0800 (PST) Date: Wed, 27 Jan 2010 02:45:27 +0200 Message-ID: From: Dan Naumov To: FreeBSD-STABLE Mailing List , dgerow@afflictions.org Content-Type: text/plain; charset=ISO-8859-1 Cc: 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 00:45:28 -0000 >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. I wouldn't worry in your particular case. A value of 2710 in 508 hours is a rate of 5,33/hour. At this rate, it's going to take you 56285 hours or 2345 days to reach 300,000 and most disks will likely function past 400,000 (over 600,000 all bets are off though). The people who need(ed) to worry were people like me, who were seeing the rate increase at a rate of 43+ per hour. - Sincerely, Dan Naumov