Return-Path: linux-nfs-owner@vger.kernel.org Received: from mail-pa0-f54.google.com ([209.85.220.54]:53929 "EHLO mail-pa0-f54.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752441AbaINNvr (ORCPT ); Sun, 14 Sep 2014 09:51:47 -0400 Received: by mail-pa0-f54.google.com with SMTP id lj1so4678834pab.13 for ; Sun, 14 Sep 2014 06:51:47 -0700 (PDT) Message-ID: <54159D6E.7010507@plexistor.com> Date: Sun, 14 Sep 2014 16:51:42 +0300 From: Boaz Harrosh MIME-Version: 1.0 To: Trond Myklebust , Boaz Harrosh CC: Christoph Hellwig , Peng Tao , Linux NFS Mailing List Subject: Re: [PATCH 8/9] pnfs/blocklayout: return layouts on setattr References: <1410362617-28018-1-git-send-email-hch@lst.de> <1410362617-28018-9-git-send-email-hch@lst.de> <20140911152553.GD6690@lst.de> <20140911154834.GA9280@lst.de> <5415740E.6030202@gmail.com> In-Reply-To: Content-Type: text/plain; charset=UTF-8 Sender: linux-nfs-owner@vger.kernel.org List-ID: On 09/14/2014 04:24 PM, Trond Myklebust wrote: > On Sun, Sep 14, 2014 at 6:55 AM, Boaz Harrosh wrote: <> > > No Boaz. I mean that it is utterly pointless and stupid to return a > layout that doesn't preallocate any resources when it isn't necessary > to do so. > "preallocate any resources" where? at the client it might not but the server might have allocated resources per lo-segment. For example a CEPH server allocates a device_id per file-lo-segment. If you lo_return a truncated segment it might be able to free that device_id. Cheers Boaz