From mboxrd@z Thu Jan 1 00:00:00 1970 From: Marc Lehmann Subject: Re: write performance difference 3.18.21/4.2.1 Date: Fri, 25 Sep 2015 01:27:20 +0200 Message-ID: <20150924232720.GA2892@schmorp.de> References: <20150923215850.GC2360@schmorp.de> <20150923231103.GA3463@schmorp.de> <20150924182836.GD40291@jaegeuk-mac02> <20150924232025.GA2242@schmorp.de> Mime-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Return-path: Received: from sog-mx-1.v43.ch3.sourceforge.com ([172.29.43.191] helo=mx.sourceforge.net) by sfs-ml-3.v29.ch3.sourceforge.com with esmtp (Exim 4.76) (envelope-from ) id 1ZfFvE-0007kD-KB for linux-f2fs-devel@lists.sourceforge.net; Thu, 24 Sep 2015 23:27:28 +0000 Received: from mail.nethype.de ([5.9.56.24]) by sog-mx-1.v43.ch3.sourceforge.com with esmtps (TLSv1:AES128-SHA:128) (Exim 4.76) id 1ZfFvC-0006pc-Mc for linux-f2fs-devel@lists.sourceforge.net; Thu, 24 Sep 2015 23:27:28 +0000 Content-Disposition: inline In-Reply-To: <20150924232025.GA2242@schmorp.de> List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: linux-f2fs-devel-bounces@lists.sourceforge.net To: Jaegeuk Kim Cc: linux-f2fs-devel@lists.sourceforge.net On Fri, Sep 25, 2015 at 01:20:25AM +0200, Marc Lehmann = wrote: > On Thu, Sep 24, 2015 at 11:28:36AM -0700, Jaegeuk Kim wrote: > > > The log starts after only 20GB had been written. Here is the status o= utput > > > at 25GB: > > > = > > > http://ue.tst.eu/734f7883107ee4dabff77602db92310b.txt > > = > > It seems about 700MB were moved by background GC. And before rebooting I did another sync, which took 130s, using 100% system time. This is the status output afterward: http://ue.tst.eu/6d0398c4184fdbef059e90a6bf454241.txt Is it normal that f2fs takes this long for a sync? What happens when, during shutdown, there is a timeout during umount and systemd shuts down anyway, or the fs doesn't get unmounted, will there be data loss because of rolling back? I am a bit concerned, because the filesystem was sitting idle for hours, and I expect a crash at that point to not lose any data due to reverting to a=A0checkpoint. -- = The choice of a Deliantra, the free code+content MORPG -----=3D=3D- _GNU_ http://www.deliantra.net ----=3D=3D-- _ generation ---=3D=3D---(_)__ __ ____ __ Marc Lehmann --=3D=3D---/ / _ \/ // /\ \/ / schmorp@schmorp.de -=3D=3D=3D=3D=3D/_/_//_/\_,_/ /_/\_\ ---------------------------------------------------------------------------= ---