From: "Gao, Yunpeng" Subject: Is it possible for the ext4/btrfs file system to pass some context related info to low level block driver? Date: Tue, 3 May 2011 10:44:07 +0800 Message-ID: Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 8BIT Cc: "linux-mmc@vger.kernel.org" To: "linux-btrfs@vger.kernel.org" , "linux-ext4@vger.kernel.org" , "linux-fsdevel@vger.kernel.org" Return-path: Content-Language: en-US Sender: linux-mmc-owner@vger.kernel.org List-Id: linux-ext4.vger.kernel.org Currently, some new storage devices have the ability to do performance optimizations according to the type of data payload - say, file system metadata, time-stamps, sequential write in some granularity, random write and so on. For example, the latest eMMC 4.5 device can support the so-called 'Context Management' and 'Data Tag Mechanism' features. By receiving the information of payload data type, the eMMC 4.5 device can improve the access rate during the following read and update operations and offer a more reliable and robust storage. And obviously, to enable these kind of advanced features of storage device, it needs not only the low level block device driver supports, but also the file system supports since files system knows more info about the data type of the payload. But currently, seems there are no file systems implemented these kind of supports yet. So, my question is, is there any plan or discussion on supporting this feature (passing data type info to low level block device driver) on file system developments? Especially for ext4/btrfs, since now they are very hot in Linux? Thanks. Regards, Yunpeng Gao