From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ted Ts'o Subject: Re: [PATCH 1/3] jbd2: allocate transaction from special cache Date: Mon, 13 Feb 2012 17:10:20 -0500 Message-ID: <20120213221020.GB21641@thunk.org> References: <1321183291-4589-1-git-send-email-xiaoqiangnk@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: linux-ext4@vger.kernel.org, Manish Katiyar To: Yongqiang Yang Return-path: Received: from li9-11.members.linode.com ([67.18.176.11]:36546 "EHLO test.thunk.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753669Ab2BMWKZ (ORCPT ); Mon, 13 Feb 2012 17:10:25 -0500 Content-Disposition: inline In-Reply-To: <1321183291-4589-1-git-send-email-xiaoqiangnk@gmail.com> Sender: linux-ext4-owner@vger.kernel.org List-ID: On Sun, Nov 13, 2011 at 07:21:29PM +0800, Yongqiang Yang wrote: > transaction_t is 136 byes under 32-bit systems. If we allocate > it from general cache, it comsumes 256 bytes. So let jbd2 allocate > it from special cache to reduce memory consumption. > > Signed-off-by: Yongqiang Yang Thanks, applied with a modified description: jbd2: allocate transaction from separate slab cache There is normally only a handful of these active at any one time, but putting them in a separate slab cache makes debugging memory corruption problems easier. Manish Katiyar also wanted this make it easier to test memory failure scenarios in the jbd2 layer. - Ted