Horton

Re: PostgreSQL, NetBSD and NFS

Manuel Bouyer <bouyer@antioche.eu.org>

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From: Manuel Bouyer <bouyer@antioche.eu.org>
To: Greg Copeland <greg@CopelandConsulting.Net>
Cc: mlw <pgsql@mohawksoft.com>, "D'Arcy J.M. Cain" <darcy@druid.net>, PostgresSQL Hackers Mailing List <pgsql-hackers@postgresql.org>, current-users@netbsd.org
Date: 2003-02-01T22:31:33Z
Lists: pgsql-hackers 
On Thu, Jan 30, 2003 at 01:27:59PM -0600, Greg Copeland wrote:
> That was going to be my question too.
> 
> I thought NFS didn't have some of the requisite file system behaviors
> (locking, flushing, etc. IIRC) for PostgreSQL to function correctly or
> reliably.

I don't know what locking sheme PostgreSQL use, but in theory it should
be possible to use it over NFS:
- a fflush()/msync() should work the same way on a NFS filesystem as on a
  local filesystem, provided the client and server implements the NFS
  protocol properly
- locking via temp files works over NFS, again provided the client and server
  implements the NFS protocol properly (this is why you can safely read your
  mailbox over NFS, for example). If PostgreSQL uses flock or fcntl, it's
  a problem.

-- 
Manuel Bouyer <bouyer@antioche.eu.org>
     NetBSD: 24 ans d'experience feront toujours la difference
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