From: Yongqiang Yang Subject: [RFC] enable ext4 allocate blocks across group boundary Date: Thu, 15 Mar 2012 08:52:35 +0800 Message-ID: Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 To: Ext4 Developers List Return-path: Received: from mail-gx0-f174.google.com ([209.85.161.174]:51203 "EHLO mail-gx0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1031430Ab2COAwg (ORCPT ); Wed, 14 Mar 2012 20:52:36 -0400 Received: by gghe5 with SMTP id e5so2502128ggh.19 for ; Wed, 14 Mar 2012 17:52:35 -0700 (PDT) Sender: linux-ext4-owner@vger.kernel.org List-ID: Hello List, Here is a proposal to enable ext4 allocate blocks across group boundary. 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. Any ideas? -- Best Wishes Yongqiang Yang