From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mondschein.lichtvoll.de ([194.150.191.11]:48378 "EHLO mail.lichtvoll.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1946789Ab2LFSyG (ORCPT ); Thu, 6 Dec 2012 13:54:06 -0500 From: Martin Steigerwald To: linux-btrfs@vger.kernel.org Subject: Re: Question about btrfs snapshot delay and rm -rf delay Date: Thu, 6 Dec 2012 19:54:04 +0100 Cc: Marc MERLIN , Sylvain Alain References: <20121206063151.GC20550@merlins.org> (sfid-20121206_101851_658481_E78E335D) In-Reply-To: <20121206063151.GC20550@merlins.org> MIME-Version: 1.0 Content-Type: Text/Plain; charset="iso-8859-1" Message-Id: <201212061954.04424.Martin@lichtvoll.de> Sender: linux-btrfs-owner@vger.kernel.org List-ID: Am Donnerstag, 6. Dezember 2012 schrieb Marc MERLIN: > On Wed, Dec 05, 2012 at 11:56:27PM -0500, Sylvain Alain wrote: > > Hi everyone, I'm running btrfs since octobre 2012 and I would like to > > understand 2 behavior that I noticed. > > > > 1. When I delete a big directory, sometimes it can hang my box for 1 > > minutes or so, it seems that's the btrfs lock my SSD. > > Doesn't directly answer your question, but if you don't have discard as a > mount option, you should try that. > > Which SSD do you have? Do normal big file writes succeed or hang too? > > My guess right now is that you don't have discard, and your drive is doing > very slow garbage collection. I had a Crucial C300 that did just that before > it ate itself and my data a month later. > Also check that your drive does not have a firmware update to remove those > hangs. Maybe also the drive does slow trims, but I doubt an Intel SSD 520 would fall into that category. In case you want to try out Sylvain, mount *without* discard option, and run fstrim manually or by cron job from time to time. Ciao, -- Martin 'Helios' Steigerwald - http://www.Lichtvoll.de GPG: 03B0 0D6C 0040 0710 4AFA B82F 991B EAAC A599 84C7