From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail144.messagelabs.com (mail144.messagelabs.com [216.82.254.51]) by kanga.kvack.org (Postfix) with ESMTP id E71216B004D for ; Wed, 29 Apr 2009 07:41:02 -0400 (EDT) Subject: Re: btrfs BUG on creating huge sparse file From: Chris Mason In-Reply-To: <20090429082151.GA15170@localhost> References: <20090407509.382219156@firstfloor.org> <20090407151010.E72A91D0471@basil.firstfloor.org> <1239210239.28688.15.camel@think.oraclecorp.com> <20090409072949.GF14687@one.firstfloor.org> <20090409075805.GG14687@one.firstfloor.org> <1239283829.23150.34.camel@think.oraclecorp.com> <20090409140257.GI14687@one.firstfloor.org> <1239287859.23150.57.camel@think.oraclecorp.com> <20090429081616.GA8339@localhost> <20090429082151.GA15170@localhost> Content-Type: text/plain Date: Wed, 29 Apr 2009 07:40:22 -0400 Message-Id: <1241005222.19174.1.camel@think.oraclecorp.com> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org To: Wu Fengguang Cc: Andi Kleen , hugh@veritas.com, npiggin@suse.de, riel@redhat.com, lee.schermerhorn@hp.com, akpm@linux-foundation.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, x86@kernel.org, "linux-btrfs@vger.kernel.org" List-ID: On Wed, 2009-04-29 at 16:21 +0800, Wu Fengguang wrote: > On Wed, Apr 29, 2009 at 04:16:16PM +0800, Wu Fengguang wrote: > > On Thu, Apr 09, 2009 at 10:37:39AM -0400, Chris Mason wrote: > [snip] > > > PagePrivate is very common. try_to_releasepage failing on a clean page > > > without the writeback bit set and without dirty/locked buffers will be > > > pretty rare. > > > > Yup. btrfs seems to tag most(if not all) dirty pages with PG_private. > > While ext4 won't. > > Chris, I run into a btrfs BUG() when doing > > dd if=/dev/zero of=/b/sparse bs=1k count=1 seek=104857512345 > > The half created sparse file is > > -rw-r--r-- 1 root root 98T 2009-04-29 14:54 /b/sparse > Or > -rw-r--r-- 1 root root 107374092641280 2009-04-29 14:54 /b/sparse > > Below is the kernel messages. I can test patches you throw at me :-) > How big was the FS you were testing this on? It works for me... -chris -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org