From: Robin Dong Subject: Re: [RFC] enable ext4 allocate blocks across group boundary Date: Thu, 15 Mar 2012 10:36:24 +0800 Message-ID: References: Mime-Version: 1.0 Content-Type: text/plain; charset=GB2312 Content-Transfer-Encoding: QUOTED-PRINTABLE Cc: Ext4 Developers List To: Yongqiang Yang Return-path: Received: from mail-yw0-f46.google.com ([209.85.213.46]:63738 "EHLO mail-yw0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755407Ab2COCgZ convert rfc822-to-8bit (ORCPT ); Wed, 14 Mar 2012 22:36:25 -0400 Received: by yhmm54 with SMTP id m54so2615958yhm.19 for ; Wed, 14 Mar 2012 19:36:24 -0700 (PDT) In-Reply-To: Sender: linux-ext4-owner@vger.kernel.org List-ID: =D4=DA 2012=C4=EA3=D4=C215=C8=D5 =C9=CF=CE=E78:52=A3=ACYongqiang Yang <= xiaoqiangnk@gmail.com> =D0=B4=B5=C0=A3=BA > Hello List, > > Here is a proposal to enable ext4 allocate blocks across group bounda= ry. > > Now ext4 allocates blocks within a single block group by locking a > group. Flex_bg puts metadata blocks together, as a result,it > enlarges contiguous blocks. So we can enable ext4 allocate blocks > within a flex block group. Inode allocation takes group lock as block > allocation, I am not sure if we should allocate inode within single > group as before. > > If we do this, then the new group boundary will be flex block group > boundary. I am not sure if it is worth doing. IMO, since the max size of one ext4-extent is just 128MB, maybe a contiguous space beyond a single block group can not be used efficiently. > > > Any ideas? > > -- > Best Wishes > Yongqiang Yang > -- > To unsubscribe from this list: send the line "unsubscribe linux-ext4"= in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html --=20 -- Best Regard Robin Dong -- 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