From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from glockenspiel.complete.org ([78.47.53.23]:35998 "EHLO glockenspiel.complete.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753475Ab3JUNr4 (ORCPT ); Mon, 21 Oct 2013 09:47:56 -0400 Message-ID: <52653084.8050106@complete.org> Date: Mon, 21 Oct 2013 08:47:48 -0500 From: John Goerzen MIME-Version: 1.0 To: Tomasz Chmielewski CC: linux-btrfs@vger.kernel.org Subject: Re: Lots of trouble hanging when rm files with many extents References: <20131021133644.172387f5@virtall.com> In-Reply-To: <20131021133644.172387f5@virtall.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Sender: linux-btrfs-owner@vger.kernel.org List-ID: On 10/20/2013 11:36 PM, Tomasz Chmielewski wrote: >>> I'll do some more tests with lots of extents to see if it's >>> reproducible here as well. >> Interestingly, I've generally had qgroups enabled here as well, >> possibly on all of these systems. Could that be the culprit? > Possibly. > > Is there a reliable way to create files with many extents? I've tried > playing with fallocate, but couldn't create files with too many extents > with it. I could do it quite reliably by storing a VirtualBox VM hard drive image there, then running a Windows Update inside the VM. Instant fragmentation ;-) Another approach could probably be to write a C program that writes 20GB to a file, then seeks to random places within it, writing chunks of data within them. I could probably whip up such a thing if the debuggers need it. John