From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: util-linux-owner@vger.kernel.org Received: from ud10.udmedia.de ([194.117.254.50]:55911 "EHLO mail.ud10.udmedia.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932908AbaDIPz7 (ORCPT ); Wed, 9 Apr 2014 11:55:59 -0400 Date: Wed, 9 Apr 2014 17:55:57 +0200 From: Markus Trippelsdorf To: Ruediger Meier Cc: util-linux@vger.kernel.org Subject: Re: [PATCH] fstrim: add systemd units Message-ID: <20140409155557.GF26270@x4> References: <1396561311-12825-1-git-send-email-thomas@archlinux.org> <20140409110251.GT22126@x2.net.home> <20140409140240.GA26270@x4> <201404091748.07452.sweet_f_a@gmx.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <201404091748.07452.sweet_f_a@gmx.de> Sender: util-linux-owner@vger.kernel.org List-ID: On 2014.04.09 at 17:48 +0200, Ruediger Meier wrote: > On Wednesday 09 April 2014, Markus Trippelsdorf wrote: > > On 2014.04.09 at 13:02 +0200, Karel Zak wrote: > > > On Wed, Apr 09, 2014 at 12:07:56PM +0200, Ruediger Meier wrote: > > > > Actually I think daily "fstrim -a" IS not a good idea for most of > > > > my systems > > > > > > install service != enable (this is important detail, I'll never > > > agree with automatically enabled services). > > > > > > BTW, why IS not a good idea for your systems? > > > > The fixed interval is problematic. There are SSD devices out there > > that suffer (their flash cells die out faster) when they get trimmed > > too often. A good rule of thumb is to trim once you have written the > > same amount as you have free space on your device. Obviously, that > > interval varies for every user (e.g. it's one week in my case). > > Is "mount -o discard" instead of fstrim interval more or less bad > regarding lifetime? It really depends on the specific SSD model. But a cron job with fstrim should do a better job in general. > And BTW does fstrim makes sense on non SSDs at all? No. (There are huge storage solutions with thin provisioning, that offer trim support.) -- Markus