Subject: Re: kqueue and NFS
To: Jaromir Dolecek <jdolecek@netbsd.org>
From: Jason R Thorpe <thorpej@wasabisystems.com>
List: tech-kern
Date: 09/28/2002 12:00:59
On Sat, Sep 28, 2002 at 08:42:24PM +0200, Jaromir Dolecek wrote:
> To make the kevent facility [*] really working properly, the NFS client
> code need to know about any file changes. This can be
> done for local system (which is easy, and I have already changes to
> do this), but the file can also change on the server by different
> client.
NFS has often had trouble with "unix semantics".
The reason that there is no callback mechanism is because NFS is stateless
(well, it's supposed to be anyway :-) .. the server doesn't know which
clients are currently active.
I don't think polling is right, either. That will generate a lot of
annoying network traffic.
Instead, I would say "only support kevents for local writes of the file",
and document this behavior for the NFS case.
--
-- Jason R. Thorpe <thorpej@wasabisystems.com>