From owner-freebsd-fs@FreeBSD.ORG Sat Jul 26 18:22:28 2008 Return-Path: Delivered-To: freebsd-fs@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id D081C1065673 for ; Sat, 26 Jul 2008 18:22:28 +0000 (UTC) (envelope-from peter.schuller@infidyne.com) Received: from smtp.infidyne.com (ds9.infidyne.com [88.80.6.206]) by mx1.freebsd.org (Postfix) with ESMTP id 95FB28FC0C for ; Sat, 26 Jul 2008 18:22:28 +0000 (UTC) (envelope-from peter.schuller@infidyne.com) Received: from c-a916e555.03-51-73746f3.cust.bredbandsbolaget.se (c-a916e555.03-51-73746f3.cust.bredbandsbolaget.se [85.229.22.169]) by smtp.infidyne.com (Postfix) with ESMTPSA id 617F18736F for ; Sat, 26 Jul 2008 20:04:47 +0200 (CEST) From: Peter Schuller To: freebsd-fs@freebsd.org Date: Sat, 26 Jul 2008 20:05:46 +0200 User-Agent: KMail/1.9.7 MIME-Version: 1.0 Content-Type: multipart/signed; boundary="nextPart1701664.oZ5f8Fbn9c"; protocol="application/pgp-signature"; micalg=pgp-sha1 Content-Transfer-Encoding: 7bit Message-Id: <200807262005.54235.peter.schuller@infidyne.com> Subject: Asynchronous writing to zvols (ZFS) X-BeenThere: freebsd-fs@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Filesystems List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 26 Jul 2008 18:22:28 -0000 --nextPart1701664.oZ5f8Fbn9c Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable Content-Disposition: inline Hello, I was finally playing around with iSCSI, having never used it before. For=20 convenience, and also because it may be a future use case for real use, I=20 used zvols for my targets. I could not get write speed above roughly 1 MB/second even in simple cases= =20 like dd:ing with an 8 MB block size, with the zvol:s on a 6-disk raidz2. Th= e=20 individual disk utilization of constituent drives remains small (< 3%).=20 Switching to a memory disk target yielded expected performance=20 characteristics. I notice that there were confirmed issues with writes to zvol:s: http://bugs.opensolaris.org/bugdatabase/view_bug.do?bug_id=3D6496356 http://bugs.opensolaris.org/bugdatabase/view_bug.do?bug_id=3D6496344 The problem is that I'm not really sure how to translate "snv_59" into=20 something that I can compare with the version of ZFS in FreeBSD. Do the=20 above "bugs" still apply to the ZFS version in FreeBSD, or am I hitting=20 something else? =2D-=20 / Peter Schuller PGP userID: 0xE9758B7D or 'Peter Schuller ' Key retrieval: Send an E-Mail to getpgpkey@scode.org E-Mail: peter.schuller@infidyne.com Web: http://www.scode.org --nextPart1701664.oZ5f8Fbn9c Content-Type: application/pgp-signature; name=signature.asc Content-Description: This is a digitally signed message part. -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.9 (FreeBSD) iEYEABECAAYFAkiLZ4IACgkQDNor2+l1i32XxQCg1XPJYeV1vIMEI3iStSrWIZW3 DcUAoJu4Q632YYqe+ZCyhZx23Znx1hMQ =GNbf -----END PGP SIGNATURE----- --nextPart1701664.oZ5f8Fbn9c--