From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755258AbZJ2QVm (ORCPT ); Thu, 29 Oct 2009 12:21:42 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754769AbZJ2QVl (ORCPT ); Thu, 29 Oct 2009 12:21:41 -0400 Received: from palinux.external.hp.com ([192.25.206.14]:45280 "EHLO mail.parisc-linux.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754159AbZJ2QVl (ORCPT ); Thu, 29 Oct 2009 12:21:41 -0400 Date: Thu, 29 Oct 2009 10:21:45 -0600 From: Matthew Wilcox To: Tejun Heo Cc: Greg Kroah-Hartman , linux-kernel@vger.kernel.org, Jesse Barnes , linux-pci@vger.kernel.org Subject: Re: [PATCH 2/3] Sysfs: Allow directories to be populated dynamically Message-ID: <20091029162145.GM10555@parisc-linux.org> References: <20091020054740.GC29158@parisc-linux.org> <20091020055021.GE29158@parisc-linux.org> <4AE9C0B0.3030304@suse.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4AE9C0B0.3030304@suse.de> User-Agent: Mutt/1.5.18 (2008-05-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Oct 29, 2009 at 05:20:00PM +0100, Tejun Heo wrote: > This will increase the size of struct sysfs_dirent by three pointers > which is considerable. Bloating the size of sysfs_dirent can waste > large amount of memory on machines with a lot of disks. No it won't. It's in a union with sysfs_inode_attrs which contains a struct iattr, which is at least 52 bytes. > The implementation looks quite scary to me. Is this the only way to > do this? It it because trying to create individual entries for msix > will end up creating too many sysfs entries? If so, how many are we > talking about? While that's the original motivation, shrinking the amount of memory taken by sysfs overall is a worthwhile achievement, don't you think? -- Matthew Wilcox Intel Open Source Technology Centre "Bill, look, we understand that you're interested in selling us this operating system, but compare it to ours. We can't possibly take such a retrograde step."