From: Theodore Ts'o Subject: Re: [PATCH 3/3] mke2fs: document bigalloc and cluster-size Date: Tue, 15 Jan 2013 14:12:54 -0500 Message-ID: <20130115191254.GD17719@thunk.org> References: <1358068095-9034-1-git-send-email-wenqing.lz@taobao.com> <1358068095-9034-3-git-send-email-wenqing.lz@taobao.com> <20130115031006.GB31857@thunk.org> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Cc: linux-ext4@vger.kernel.org, Zheng Liu To: Zheng Liu Return-path: Received: from li9-11.members.linode.com ([67.18.176.11]:43552 "EHLO imap.thunk.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755589Ab3AOTM5 (ORCPT ); Tue, 15 Jan 2013 14:12:57 -0500 Content-Disposition: inline In-Reply-To: <20130115031006.GB31857@thunk.org> Sender: linux-ext4-owner@vger.kernel.org List-ID: On Mon, Jan 14, 2013 at 10:10:06PM -0500, Theodore Ts'o wrote: > On Sun, Jan 13, 2013 at 05:08:15PM +0800, Zheng Liu wrote: > > From: Zheng Liu > >=20 > > Bigalloc feature has been used for a long time, but the documentati= on in mke2fs > > is still missing. So add it. > >=20 > > Signed-off-by: Zheng Liu >=20 > Applied (with some changes to improve the english/wording). BTW, I used the following modified text: bigalloc This feature enables clustered allocation, = so that the unit of allocation is a power of two num= ber of blocks. That is, each bit in the what had= tradi=E2=80=90 tionally been known as the block allocation = bitmap now indicates whether a cluster is in use = or not, where a cluster is by default composed of 16 = blocks. This feature can decrease the time spent o= n doing block allocation and brings smaller fragmen= tation, especially for large files. The size can be= speci=E2=80=90 fied using the -C option. Warning: The bigalloc feature is still under = devel=E2=80=90 opment, and may not be fully supported wi= th your kernel or may have various bugs. Please see = the web page http://ext4.wiki.kernel.org/index.php/B= igalloc for details. And I populated the page on the ext4 wiki so that when we finally fix the delalloc/bigalloc problem, we can update the ext4 wiki to reflect this. - Ted -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" i= n the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html