From mboxrd@z Thu Jan 1 00:00:00 1970 From: James Bottomley Subject: Re: Race to power off harming SATA SSDs Date: Mon, 10 Apr 2017 16:57:55 -0700 Message-ID: <1491868675.2473.22.camel@HansenPartnership.com> References: <20170410232118.GA4816@khazad-dum.debian.net> <20170410235206.GA28603@wtj.duckdns.org> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20170410235206.GA28603@wtj.duckdns.org> Sender: linux-scsi-owner@vger.kernel.org To: Tejun Heo , Henrique de Moraes Holschuh Cc: linux-kernel@vger.kernel.org, linux-scsi@vger.kernel.org, linux-ide@vger.kernel.org, Hans de Goede List-Id: linux-ide@vger.kernel.org On Tue, 2017-04-11 at 08:52 +0900, Tejun Heo wrote: [...] > > Any comments? Any clues on how to make the delay "smarter" to > > trigger only once during platform shutdown, but still trigger per > > -device when doing per-device hotswapping ? > > So, if this is actually an issue, sure, we can try to work around; > however, can we first confirm that this has any other consequences > than a SMART counter being bumped up? I'm not sure how meaningful > that is in itself. Seconded; especially as the proposed patch is way too invasive: we run single threaded on shutdown and making every disk wait 1s is going to drive enterprises crazy. I'm with Tejun: If the device replies GOOD to SYNCHRONIZE CACHE, that means we're entitled to assume all written data is safely on non-volatile media and any "essential housekeeping" can be redone if the power goes away. James