From: Theodore Tso Subject: Re: EXT4 ENOSPC Bug Date: Tue, 2 Dec 2008 11:47:09 -0500 Message-ID: <20081202164709.GC18162@mit.edu> References: <200811291418.24672.andres@anarazel.de> <200812012116.08510.andres@anarazel.de> <20081202075712.GA16172@mit.edu> <200812021559.05103.andres@anarazel.de> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Andreas Dilger , LKML , linux-ext4@vger.kernel.org To: Andres Freund Return-path: Received: from www.church-of-our-saviour.org ([69.25.196.31]:49631 "EHLO thunker.thunk.org" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1755529AbYLBQrN (ORCPT ); Tue, 2 Dec 2008 11:47:13 -0500 Content-Disposition: inline In-Reply-To: <200812021559.05103.andres@anarazel.de> Sender: linux-ext4-owner@vger.kernel.org List-ID: On Tue, Dec 02, 2008 at 03:58:53PM +0100, Andres Freund wrote: > Ok. The system now runs (without problems) with the patch enabled and I can > get the debug output. > 30 Minutes after boot the system still returns to zero dirty blocks and the > free blocks seem to stay in a sensible range. > I will let it run for a while and report back if either something interesting > happens or the problem reappears and I am seeing no significant amount of dirty > blocks. You say you are using Postgres, right? Something you might try to see if it triggers the problem it is creating a new database and then restoring some database dump/backup into that new database. Some databases expand into a new table space (or whatever terminology Postgres uses) by random writes into a sparse portion of the file. This could be triggering the problem, or at least trigger the problem more quickly. The other thing I wanted to ask is whether "df" was showing the 37% in-use statistic at the time, or was that after you rebooted. And although I hate to ask it, you're sure this isn't the standard "delete an in-use file but not get the space back" Unix trap, right? Thanks, regards, - Ted