From mboxrd@z Thu Jan 1 00:00:00 1970 From: Vyacheslav Dubeyko Subject: Re: [PATCH 1/1] nilfs2: add mount option that reduces super block writes Date: Thu, 30 Jan 2014 14:27:15 +0300 Message-ID: References: <75ceb45c464097ab556baacf2d15d6ae4b792bb2.1391048231.git.andreas.rohner@gmx.net> <127C78C3-9D47-439C-9639-263BC453D98D@dubeyko.com> <52E9EB06.1000504@gmx.net> <8DBE8E18-F678-44B0-A6A6-5AFEC227AA86@dubeyko.com> <52EA2002.1030809@gmx.net> Mime-Version: 1.0 (Apple Message framework v1085) Content-Transfer-Encoding: 8BIT Return-path: DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=dubeyko.com; s=default; h=To:References:Message-Id:Content-Transfer-Encoding:Cc:Date:In-Reply-To:From:Content-Type:Mime-Version:Subject; bh=xkA3GYavmHjdP8V6hXw2hSKBHMUQgTso5uQ1xM3MGt0=; b=rwUoskKNz2A0iOxE/2BC6e18pB4hQ48azMWsAhObxg/F+Zbd36qFcOXtjhBSh1Nyx4LNvMJy+8Awp/tG4FtP98PY64qFCZ/Tttkgis67lJXuHJvjJmMYIL13JtRNFxq3; In-Reply-To: <52EA2002.1030809-hi6Y0CQ0nG0@public.gmane.org> Sender: linux-nilfs-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-ID: Content-Type: text/plain; charset="us-ascii" To: Andreas Rohner Cc: linux-nilfs-u79uwXL29TY76Z2rM5mHXA@public.gmane.org On Jan 30, 2014, at 12:48 PM, Andreas Rohner wrote: > > I have just finished a test with my 100 GB HDD and SSD. I filled it > with dd until it was 100% full. Then I cut power to the machine and > timed the following mount operation: > > 100GB HDD: > time sudo mount -o bad_ftl /dev/sda1 /mnt/ > > real 1m21.068s > user 0m0.020s > sys 0m0.770s > > 100GB SSD: > time sudo mount -o bad_ftl /dev/sdc1 /mnt/ > > real 0m2.124s > user 0m0.010s > sys 0m0.243s > > So it looks quite bad for hard drives. To scan a 1 TB hard drive would > take 13 minutes. > > But a 1 TB SSD would only take 20 seconds! > I think that it will be good to have comparable results for the same environment. I mean, for example, measurement in different situations for SSD (without your patch and this your patch). How much time do you need for scanning the whole SSD by your approach? I think that comparison of linear scanning results for the whole SSD drive and for sudden power-off situation can provide basis for consideration. But sudden power-off situation can be different, I suppose. Thanks, Vyacheslav Dubeyko. > I will test one of my SD cards next. > > Regards, > Andreas Rohner -- To unsubscribe from this list: send the line "unsubscribe linux-nilfs" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html