From owner-freebsd-fs@FreeBSD.ORG Tue Apr 19 08:31:00 2011 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 6084B106564A for ; Tue, 19 Apr 2011 08:31:00 +0000 (UTC) (envelope-from borjam@sarenet.es) Received: from proxypop01.sare.net (proxypop01.sare.net [194.30.0.28]) by mx1.freebsd.org (Postfix) with ESMTP id 1DB278FC08 for ; Tue, 19 Apr 2011 08:30:59 +0000 (UTC) Received: from [172.16.1.55] (ssglan.sare.net [192.148.167.100]) by proxypop01.sare.net (Postfix) with ESMTPA id AADD763E8D9; Tue, 19 Apr 2011 10:15:26 +0200 (CEST) Mime-Version: 1.0 (Apple Message framework v1084) Content-Type: text/plain; charset=us-ascii From: Borja Marcos In-Reply-To: Date: Tue, 19 Apr 2011 10:15:26 +0200 Content-Transfer-Encoding: quoted-printable Message-Id: <3596CB9B-7996-404B-AD34-D3A8DFD67FD4@sarenet.es> References: <4DAC7811.3090407@ukr.net> <4DAC96EA.8080505@ukr.net> To: Artem Belevich X-Mailer: Apple Mail (2.1084) Cc: freebsd-fs@freebsd.org Subject: Re: Prompt to synchronize two volumes 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: Tue, 19 Apr 2011 08:31:00 -0000 On Apr 18, 2011, at 10:15 PM, Artem Belevich wrote: > They mentioned performance. mbuffer in-between receive and send makes > *a lot* of difference as long as you provide few seconds worth of > buffering at the rate your filesystems can sustain. I think the > authors of the page above just didn't use large enough buffer. You > would probably have to experiment yourself. In my case of ~3TB > transfer (mostly large files), I ended up with "mbuffer -m512M". I > also used mbuffer's built-in network transfer mechanism (see mbuffer's > -I/-O options) as at high data rates ssh became the bottleneck. Moreover, although ZFS receive seems to be robust in case a replication = stream is interrupted, I find it much more safer to move the stream = beforehand, and start the zfs receive with a complete stream. Borja.