From: Milan Broz Subject: Re: aesni-intel slower than aes-x86_64 Date: Mon, 12 Apr 2010 14:41:46 +0200 Message-ID: <4BC3150A.1080905@redhat.com> References: <693236.82640.qm@web45101.mail.sp1.yahoo.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: linux-crypto@vger.kernel.org To: john terragon Return-path: Received: from mx1.redhat.com ([209.132.183.28]:5835 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751151Ab0DLMls (ORCPT ); Mon, 12 Apr 2010 08:41:48 -0400 In-Reply-To: <693236.82640.qm@web45101.mail.sp1.yahoo.com> Sender: linux-crypto-owner@vger.kernel.org List-ID: On 04/12/2010 12:52 AM, john terragon wrote: > My system has a core i5 520M and supports AES-NI. I wanted to do a > rude performance test and so I ran these commands on a small (4GB) partition and on the dm-crypt device backed by it: > > 1) using the aesni-intel module: dd if=/dev/dev/mapper/vol of=/dev/null bs=4k > 2) using only the generic aes-x86_64 module: dd if=/dev/dev/mapper/vol > of=/dev/null bs=4k > 3) dd if=/dev/sda4 of=/dev/null bs=4k > > What I got kind of surprised me: > 1) ~ 67 MB/sec, with a low cpu load by kcryptd > 2) ~ 79 MB/sec, with a higher cpu load by kcryptd > 3) ~ 81 MB/sec Just curious - is it the same if you add iflag=direct? Also try larger block size bs=1M etc. Milan