From owner-freebsd-questions@freebsd.org Sun Sep 27 11:10:47 2015 Return-Path: Delivered-To: freebsd-questions@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id A410CA08CDA for ; Sun, 27 Sep 2015 11:10:47 +0000 (UTC) (envelope-from freebsd@edvax.de) Received: from mx01.qsc.de (mx01.qsc.de [213.148.129.14]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id 6966ADA2 for ; Sun, 27 Sep 2015 11:10:46 +0000 (UTC) (envelope-from freebsd@edvax.de) Received: from r56.edvax.de (port-92-195-125-111.dynamic.qsc.de [92.195.125.111]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by mx01.qsc.de (Postfix) with ESMTPS id 085473CC35; Sun, 27 Sep 2015 13:10:37 +0200 (CEST) Received: from r56.edvax.de (localhost [127.0.0.1]) by r56.edvax.de (8.14.5/8.14.5) with SMTP id t8RBAaeF002015; Sun, 27 Sep 2015 13:10:36 +0200 (CEST) (envelope-from freebsd@edvax.de) Date: Sun, 27 Sep 2015 13:10:36 +0200 From: Polytropon To: "William A. Mahaffey III" Cc: FreeBSD Questions !!!! Subject: Re: dd question Message-Id: <20150927131036.c6b2d9ce.freebsd@edvax.de> In-Reply-To: <56073915.6030707@hiwaay.net> References: <5606A4FF.4090105@hiwaay.net> <56073915.6030707@hiwaay.net> Reply-To: Polytropon Organization: EDVAX X-Mailer: Sylpheed 3.1.1 (GTK+ 2.24.5; i386-portbld-freebsd8.2) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 27 Sep 2015 11:10:47 -0000 On Sat, 26 Sep 2015 19:37:51 -0453.75, William A. Mahaffey III wrote: > Update: I tried the dd again w/ 'bs=1m' & it worked much faster: It's a more "native" block size suited for the devices in question. 512 blocks aren't much common anymore. Depending on devicees and buses, other sizes (like bs=10m) could also achieve higher speeds for processing. > The 'ctrl-T' did not in fact return anything, but the 'killall -SIGINFO > dd' from another shell window did. 3.4-ish MB/s is quite usable, so all > appears well. Ctrl+T works on FreeBSD's dd, but as far as I remember, not on Linux's where I had to do the "SIGINFO trick". You should see something like this: % dd if=/dev/zero of=/dev/null bs=1m {^T} load: 0.12 cmd: dd 2011 [running] 2.50r 0.01u 2.41s 21% 1944k 19109+0 records in 19109+0 records out 20037238784 bytes transferred in 2.499758 secs (8015671414 bytes/sec) {^C} 24797+0 records in 24797+0 records out 26001539072 bytes transferred in 3.239702 secs (8025904599 bytes/sec) % It's the same format as the final status report, prefixed by some runtime and load information -- Polytropon Magdeburg, Germany Happy FreeBSD user since 4.0 Andra moi ennepe, Mousa, ...