Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1030452AbWHXSyM (ORCPT ); Thu, 24 Aug 2006 14:54:12 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1030457AbWHXSyM (ORCPT ); Thu, 24 Aug 2006 14:54:12 -0400 Received: from pentafluge.infradead.org ([213.146.154.40]:47315 "EHLO pentafluge.infradead.org") by vger.kernel.org with ESMTP id S1030452AbWHXSyL (ORCPT ); Thu, 24 Aug 2006 14:54:11 -0400 Date: Thu, 24 Aug 2006 19:53:42 +0100 From: Christoph Hellwig To: Badari Pulavarty Cc: Herbert Xu , akpm@osdl.org, lkml , ext2-devel Subject: Re: [RFC][PATCH] Manage jbd allocations from its own slabs Message-ID: <20060824185342.GA20935@infradead.org> Mail-Followup-To: Christoph Hellwig , Badari Pulavarty , Herbert Xu , akpm@osdl.org, lkml , ext2-devel References: <1156374495.30517.5.camel@dyn9047017100.beaverton.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1156374495.30517.5.camel@dyn9047017100.beaverton.ibm.com> User-Agent: Mutt/1.4.2.1i X-SRS-Rewrite: SMTP reverse-path rewritten from by pentafluge.infradead.org See http://www.infradead.org/rpr.html Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 917 Lines: 22 On Wed, Aug 23, 2006 at 04:08:15PM -0700, Badari Pulavarty wrote: > Hi, > > Here is the fix to "bh: Ensure bh fits within a page" problem > caused by JBD. > > BTW, I realized that this problem can happen only with 1k, 2k > filesystems - as 4k, 8k allocations disable slab debug > automatically. But for completeness, I created slabs for those > also. > > What do you think ? I ran basic tests and things are fine. Why can't you just use alloc_page? I bet the whole slab overhead eats more memory than what's wasted when using alloc_pages. Especially as the typical usecase is a 4k blocks filesystem with 4k pagesize where the overhead of alloc_page is non-existant. - 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/