From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from relay.sgi.com (relay1.corp.sgi.com [137.38.102.111]) by oss.sgi.com (Postfix) with ESMTP id 808697F3F for ; Thu, 19 Mar 2015 21:27:42 -0500 (CDT) Received: from cuda.sgi.com (cuda2.sgi.com [192.48.176.25]) by relay1.corp.sgi.com (Postfix) with ESMTP id 5FFA08F8066 for ; Thu, 19 Mar 2015 19:27:39 -0700 (PDT) Received: from Ishtar.hs.tlinx.org (ishtar.tlinx.org [173.164.175.65]) by cuda.sgi.com with ESMTP id xyWA4HWtqcK60uPo (version=TLSv1 cipher=AES256-SHA bits=256 verify=NO) for ; Thu, 19 Mar 2015 19:27:34 -0700 (PDT) Message-ID: <550B858D.4030003@tlinx.org> Date: Thu, 19 Mar 2015 19:27:25 -0700 From: Linda Walsh MIME-Version: 1.0 Subject: Re: [PATCH] mkfs: default to CRC enabled filesystems References: <1426720967-8215-1-git-send-email-david@fromorbit.com> In-Reply-To: <1426720967-8215-1-git-send-email-david@fromorbit.com> List-Id: XFS Filesystem from SGI List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="us-ascii"; Format="flowed" Errors-To: xfs-bounces@oss.sgi.com Sender: xfs-bounces@oss.sgi.com To: Dave Chinner Cc: xfs@oss.sgi.com Dave Chinner wrote: > From: Dave Chinner > > It's time to change the mkfs defaults to enable CRCs for all new > filesystems. --- "Sounds good", but what exactly is CRC'ed? I.e. all data? Or how much data/second would I expect to 'need' CRC'ing? Some quick timing stuff: > time dd if=/dev/zero of=1G bs=1M count=1024 oflag=direct 1024+0 records in 1024+0 records out 1073741824 bytes (1.1 GB) copied, 1.76947 s, 607 MB/s 1.77sec 0.00usr 0.50sys (28.38% cpu) > dropcaches 76.34sec 0.00usr 69.22sys (90.69% cpu) Ishtar:law/bin> time crc32 1G ## no cache 5B64C2B0 6.67sec 3.85usr 0.94sys (71.82% cpu) > time crc32 1G ## in cache 5B64C2B0 4.00sec 3.57usr 0.42sys (100.00% cpu) (using Xeon X5660 @ 2.80GHz) _______________________________________________ xfs mailing list xfs@oss.sgi.com http://oss.sgi.com/mailman/listinfo/xfs