[OpenAFS] Re: Change in volume status during vos dump in OpenAFS 1.6.x

[Jeffrey Altman]

This is a cryptographically signed message in MIME format.

--------------ms050307070005060206070606
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: quoted-printable

On 3/14/2013 7:11 AM, Andy Malato wrote:
>=20
> ! Date: Wed, 13 Mar 2013 22:57:02 -0400
> ! From: Jeffrey Altman <jaltman@your-file-system.com>
> ! To: matthew.hoskins@njit.edu
> ! Cc: openafs-info@openafs.org
> ! Subject: Re: [OpenAFS] Re: Change in volume status during vos dump in=
 OpenAFS
> !     1.6.x
> !=20
> ! Matt:
> !=20
> ! Have you looked at the man pages?
> !=20
> !   http://docs.openafs.org/Reference/index
> !=20
> ! The pages for "fs listquota", "fs quota", "fs setquota", "fs setvol",=

> ! "vos clone", "vos copy", "vos create", "vos examine", "vos move", "vo=
s
> ! partinfo", and "vos shadow" include the following text:
> !=20
> ! "Currently, the maximum quota for a volume is 2 terabytes (2^41 bytes=
).
> ! Note that this only affects the volume's quota; a volume may grow muc=
h
> ! larger if the volume quota is disabled. However, volumes over 2
> ! terabytes in size may be impractical to move, and may have their size=

> ! incorrectly reported by some tools, such as L<fs_listquota(1)>."
>=20
> So while a volume can grow to more than 2 terabytes in size, the variou=
s=20
> tools may not work correctly with volumes this large ?

The only restrictions are:

 * once you want a volume to be larger than 2TB you cannot
   restrict its size.

 * applications that query the amount of free space with be
   told 2TB until such time as the amount of free space drops
   below 2TB

> Are there any
> plans to address these issues and to allow quotas larger than than 2tb =
?

Protocol changes are required to report larger sizes, larger volume-id
ranges, larger vnode-id ranges, 64-bit timestamps, etc.  The process of
upgrading all of these items has been referred to as "RPC Refresh".

  http://gerrit.openafs.org/#change,4573

 Your File System, Inc., at the 2012 European AFS and Kerberos
Conference, announced its plans for YFS 1.0 which will address all of
the name space issues along with the performance issues necessary to
address data sets that large.

http://conferences.inf.ed.ac.uk/eakc2012/slides/Announcing-YFS-1.0-Euro-A=
FS-2012.pdf

http://conferences.inf.ed.ac.uk/eakc2012/videos/eakc2012-yfs-altman.mp4


> As more and more researchers continue to work with big data, the reques=
t
> for multi terabyte volumes is becoming more frequent.  We are starting
> to get requests from researchers for volumes in the range of 5 to 7TB
> and we expect that future requests will probably be even larger. =20
>=20
> From what I read here it appears that AFS may be "impractical" to
> support large datasets of this size?  Can you (or anyone else) confirm
> other sites that are using AFS to support the use of big data ?

There are certainly sites that are using volumes larger than 8TB.  What
becomes impractical at that size is moving the volumes between servers
in any reasonable period of time.  Depending upon the number of files
and directories that make up the data eventually you will begin to
exhaust the per volume vnode pool.

If you need to apply limits on the size of the volume you can do so by
allocating partitions of the size you want and storing on AFS volume on
each.

In the end the question is why does the volume need to be one volume as
opposed to splitting the data across multiple volumes that are mounted.

Jeffrey Altman



--------------ms050307070005060206070606
Content-Type: application/pkcs7-signature; name="smime.p7s"
Content-Transfer-Encoding: base64
Content-Disposition: attachment; filename="smime.p7s"
Content-Description: S/MIME Cryptographic Signature
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=
--------------ms050307070005060206070606--