From: Andreas Dilger Subject: Re: Extended file stat: Splitting file- and fs-specific info? Date: Thu, 10 May 2012 10:05:28 -0600 Message-ID: <3DA7C6A5-E47C-47D4-BFBB-3E608492BD0B@dilger.ca> References: <73759631-F1E4-4352-9FE6-E9F576F793FB@gmail.com> <20120419140558.17272.74360.stgit@warthog.procyon.org.uk> <16281.1336508382@redhat.com> <20120509002420.GL5091@dastard> <14477.1336641794@redhat.com> Mime-Version: 1.0 (Apple Message framework v1084) Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: Andreas Dilger , Dave Chinner , "bfields-uC3wQj2KruNg9hUCZPvPmw@public.gmane.org" , "smfrench-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org" , "ben-/+tVBieCtBitmTQ+vhA3Yw@public.gmane.org" , "Trond.Myklebust-HgOvQuBEEgTQT0dZR+AlfA@public.gmane.org" , "roland-/Z5OmTQCD9xF6kxbq+BtvQ@public.gmane.org" , "linux-fsdevel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , "linux-nfs-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , "linux-cifs-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , "samba-technical-w/Ol4Ecudpl8XjKLYN78aQ@public.gmane.org" , "linux-ext4-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , "linux-api-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , "libc-alpha-9JcytcrH/bA+uJoB2kUjGw@public.gmane.org" To: David Howells Return-path: In-Reply-To: <14477.1336641794-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org> Sender: linux-cifs-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: linux-ext4.vger.kernel.org On 2012-05-10, at 3:23 AM, David Howells wrote: > Andreas Dilger wrote: >> The main question I have about these fields is what the difference is >> between st_blksize and st_alloc_blksize? > > I would assume that st_blksize is some ideal I/O size, not the > allocation block size. But there are several optimal IO sizes, so unless there is a clear description of what each of these fields is intended to be used for, it doesn't make sense to add them in. > Dave Chinner might be able to answer better as he suggested these > I/O information fields. > > David Cheers, Andreas