From: Eric Sandeen Subject: Re: [PATCH] ext4: Enable delalloc and mballoc by default. Date: Wed, 24 Oct 2007 16:15:36 -0500 Message-ID: <471FB5F8.1090805@redhat.com> References: <1193244441-10149-1-git-send-email-aneesh.kumar@linux.vnet.ibm.com> <1193244441-10149-2-git-send-email-aneesh.kumar@linux.vnet.ibm.com> <1193244441-10149-3-git-send-email-aneesh.kumar@linux.vnet.ibm.com> <1193244441-10149-4-git-send-email-aneesh.kumar@linux.vnet.ibm.com> <1193244441-10149-5-git-send-email-aneesh.kumar@linux.vnet.ibm.com> <1193244441-10149-6-git-send-email-aneesh.kumar@linux.vnet.ibm.com> <471F7F41.6080800@redhat.com> <20071024210639.GC26078@webber.adilger.int> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: "Aneesh Kumar K.V" , linux-ext4@vger.kernel.org To: Andreas Dilger Return-path: Received: from mx1.redhat.com ([66.187.233.31]:39270 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755260AbXJXVQD (ORCPT ); Wed, 24 Oct 2007 17:16:03 -0400 In-Reply-To: <20071024210639.GC26078@webber.adilger.int> Sender: linux-ext4-owner@vger.kernel.org List-Id: linux-ext4.vger.kernel.org Andreas Dilger wrote: > On Oct 24, 2007 12:22 -0500, Eric Sandeen wrote: >> Aneesh Kumar K.V wrote: >>> @@ -1279,6 +1280,9 @@ clear_qf_name: >>> case Opt_delalloc: >>> set_opt (sbi->s_mount_opt, DELALLOC); >>> break; >> If delalloc, mballoc, extents are the new defaults, is there a reason to >> keep them as options? When would you need to specify -o extents, now, >> for example? (though my brain is fuzzy today, maybe I'm missing >> something) If this were not a filesystem ending in "dev" I could see >> keeping it for compatibility with existing fstabs.... > > It is useful to be able to mount w/o extents/delalloc/mballoc for perf > testing and functional testing of the block-mapped file path in ext4. > Also, some users might want the ability to use features of ext4 w/o > the incompatibility of extents. Right, I understand the reason for noextents, nodelalloc, nomballoc. Above, I ask what is the point of having the *defaults* (extents, delalloc, mballoc) as mount options? -Eric