From owner-freebsd-fs@FreeBSD.ORG Thu Jun 18 18:55:03 2015 Return-Path: Delivered-To: freebsd-fs@hub.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTPS id E9AAD130 for ; Thu, 18 Jun 2015 18:55:03 +0000 (UTC) (envelope-from ticso@cicely7.cicely.de) Received: from raven.bwct.de (raven.bwct.de [85.159.14.73]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client CN "raven.bwct.de", Issuer "BWCT" (not verified)) by mx1.freebsd.org (Postfix) with ESMTPS id 80650D00 for ; Thu, 18 Jun 2015 18:55:02 +0000 (UTC) (envelope-from ticso@cicely7.cicely.de) Received: from mail.cicely.de ([10.1.1.37]) by raven.bwct.de (8.13.4/8.13.4) with ESMTP id t5IIsbCn056512 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=FAIL) for ; Thu, 18 Jun 2015 20:54:42 +0200 (CEST) (envelope-from ticso@cicely7.cicely.de) Received: from cicely7.cicely.de (cicely7.cicely.de [10.1.1.9]) by mail.cicely.de (8.14.5/8.14.4) with ESMTP id t5IIsVU5014150 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO); Thu, 18 Jun 2015 20:54:31 +0200 (CEST) (envelope-from ticso@cicely7.cicely.de) Received: from cicely7.cicely.de (localhost [127.0.0.1]) by cicely7.cicely.de (8.14.2/8.14.2) with ESMTP id t5IIsVTD029470; Thu, 18 Jun 2015 20:54:31 +0200 (CEST) (envelope-from ticso@cicely7.cicely.de) Received: (from ticso@localhost) by cicely7.cicely.de (8.14.2/8.14.2/Submit) id t5IIsVdq029469; Thu, 18 Jun 2015 20:54:31 +0200 (CEST) (envelope-from ticso) Date: Thu, 18 Jun 2015 20:54:31 +0200 From: Bernd Walter To: freebsd-fs@freebsd.org Cc: Bernd Walter Subject: reads on inactive zpools Message-ID: <20150618185430.GA27522@cicely7.cicely.de> Reply-To: ticso@cicely.de Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline X-Operating-System: FreeBSD cicely7.cicely.de 7.0-STABLE i386 User-Agent: Mutt/1.5.11 X-Spam-Status: No, score=-2.9 required=5.0 tests=ALL_TRUSTED=-1, BAYES_00=-1.9, T_RP_MATCHES_RCVD=-0.01 autolearn=ham version=3.3.0 X-Spam-Checker-Version: SpamAssassin 3.3.0 (2010-01-18) on spamd.cicely.de X-BeenThere: freebsd-fs@freebsd.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: Filesystems List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 18 Jun 2015 18:55:04 -0000 I have multiple zpools with USB drives. Under normal conditions everything is idle as it should. But when I zfs send | zfs receive from one pool to another the unrelated pools have one read/s on each disk. Once the zfs send/receive is stopped the reads to the unrelated pools also stop. Size of the unexpected reads varying below 8k, usually 7.xk, but I've also seen 4.xk. The read sizes on all disks of all pools are identic. -- B.Walter http://www.bwct.de Modbus/TCP Ethernet I/O Baugruppen, ARM basierte FreeBSD Rechner uvm.