From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.saout.de ([127.0.0.1]) by localhost (mail.saout.de [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id rgIjPqETq-w6 for ; Mon, 18 Mar 2013 09:37:05 +0100 (CET) Received: from awesome.dsw2k3.info (awesome.dsw2k3.info [IPv6:2a01:198:661:1f::3]) (using TLSv1 with cipher ADH-AES256-SHA (256/256 bits)) (No client certificate requested) by mail.saout.de (Postfix) with ESMTPS for ; Mon, 18 Mar 2013 09:37:04 +0100 (CET) Date: Mon, 18 Mar 2013 09:37:00 +0100 From: Matthias Schniedermeyer Message-ID: <20130318083700.GA28049@citd.de> References: <20130317225516.GA6053@citd.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Subject: Re: [dm-crypt] unusual writing speeds when benchmark speeds are high enough List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: ".. ink .." Cc: dm-crypt@saout.de On 18.03.2013 02:42, .. ink .. wrote: > I would say, there are quite a few details missing. > > Hardware, Software? > > 28.4 MB/s also isn't what i would call fast, what is that? > > > > The person responded and this is his computer spec: > > intel core 2 duo e8500 > 2 gb ram > 2x 80 GB HDD western digital 7,200 RPM > Kernel 3.2.18-pclos3.bfq > > 32bit os > > No LVM volume or RAID stuff,the test was done from the user home directory. > > What speed do you get from "dd" command?. People usually say the speeds i > post are not high enough but i do not remember anybody saying what speeds > are normal,expected. My newest acquisition (got it friday), a 7200RPM HDD, does between 190MB/s (outer rim) and 90MB/s (inner rim). The performance i got out of it yesterday, when i tried the dd command, was 137MB/s (and 3.1 GB/s for the version without conv=fsync). The HDD before that, a "green" model with around 5400 RPM, does between 130MB/s and 60MB/s. The best performance i usually see in reality is about 110MB/s, but it depends on where the files are written to and also where the source-file was placed on the source-HDD, so in the worst-case is about 60MB/s. The SSD i have can reach (with encryption) about 400MB/s, but that is best-case performance when all moons are aligned. I haven't really benchmarked the real-world performance, the dd-example (with conv=fsync) only got 88MB/s. -- Matthias