Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261549AbVAXRtP (ORCPT ); Mon, 24 Jan 2005 12:49:15 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261544AbVAXRtP (ORCPT ); Mon, 24 Jan 2005 12:49:15 -0500 Received: from [83.102.214.158] ([83.102.214.158]:63970 "EHLO gw.home.net") by vger.kernel.org with ESMTP id S261547AbVAXRs4 (ORCPT ); Mon, 24 Jan 2005 12:48:56 -0500 X-Comment-To: "Stephen C. Tweedie" To: "Stephen C. Tweedie" Cc: Alex Tomas , linux-kernel , "ext2-devel@lists.sourceforge.net" , Andrew Morton Subject: Re: [Ext2-devel] [PATCH] JBD: fix against journal overflow References: <1106588589.2103.116.camel@sisko.sctweedie.blueyonder.co.uk> From: Alex Tomas Organization: HOME Date: Mon, 24 Jan 2005 20:47:35 +0300 In-Reply-To: <1106588589.2103.116.camel@sisko.sctweedie.blueyonder.co.uk> (Stephen C. Tweedie's message of "Mon, 24 Jan 2005 17:43:09 +0000") Message-ID: User-Agent: Gnus/5.110002 (No Gnus v0.2) Emacs/21.3 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1231 Lines: 37 >>>>> Stephen C Tweedie (SCT) writes: SCT> I don't see how that "limit" is relevant here. wbuf is nothing but the SCT> size of the IO batches we pass to ll_rw_block() during that commit SCT> phase. j_free affects the total size of space the *entire* commit has SCT> to run into, and (as akpm has commented with a big marker beside it) SCT> start_this_handle() reserves a *lot* of headroom for the extra space SCT> that may be needed for transaction metadata. /* If there's no more to do, or if the descriptor is full, let the IO rip! */ if (bufs == ARRAY_SIZE(wbuf) || commit_transaction->t_buffers == NULL || space_left < sizeof(journal_block_tag_t) + 16) { .... /* Force a new descriptor to be generated next time round the loop. */ descriptor = NULL; bufs = 0; ------------------------^^^^^^^^^^^^^^^^^^^ SCT> Have you really seen this patch make a difference in testing? of course - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/