From: Round Robinjp Subject: Re: flashing large eMMC partitions with ext4 Date: Thu, 28 Jul 2011 03:08:26 +0900 (JST) Message-ID: <296456.55216.qm@web4205.mail.ogk.yahoo.co.jp> References: <134141.91415.qm@web4210.mail.ogk.yahoo.co.jp> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8BIT Cc: linux-ext4@vger.kernel.org To: Robinjp Round , Ted Ts'o , Andreas Dilger , Amir Goldstein , Yongqiang Yang Return-path: Received: from web4205.mail.ogk.yahoo.co.jp ([124.83.212.25]:36595 "HELO web4205.mail.ogk.yahoo.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1752337Ab1G0SIa convert rfc822-to-8bit (ORCPT ); Wed, 27 Jul 2011 14:08:30 -0400 In-Reply-To: <134141.91415.qm@web4210.mail.ogk.yahoo.co.jp> Sender: linux-ext4-owner@vger.kernel.org List-ID: I have got some nice ideas from you. I summarize them here and add some comments. o Idea from Andreas Create minimal image, flash write, then resize2fs -> Very straight forward idea. -> Post-processing after flash writing adds some difficulties. o Idea from Ted Zero-fill the non-used blocks. Make the flash writer write only non-zero blocks. -> Very straight forward idea. -> Flash writer needs to support this. o Idea from Amir Set flex_bg to 32. Set sparse_super. Allocate journal from group 0 (feasibility unclear) Truncate the image. -> Feasibility and effectiveness is unclear. -> Good side is legacy flash writer can be used. o Idea from Yongqiang Delete journal before flash write and later add it back. -> Post-processing after flash writing adds some difficulties. I will examine all of these to find out a suitable solution. Thanks Round