Re: NFS

[Jukka Marin <jmarin%embedtronics.fi@localhost>]

On Thu, Jul 09, 2009 at 02:34:39AM -0400, Matthew Mondor wrote:
> Interestingly I've been using TCP for NFS for a long time (years), yet
> lately I tend to often see these (it might be since the
> netbsd-4->netbsd-5 upgrade, but I'm not sure.  Since most of the time
> this seemed harmless I didn't look into it much until now):
> 
> nfs server foo not responding
> nfs server foo is alive again
> 
> In all cases, the delay between the two is quite short, in the order of
> a second or two at most.  Sometimes these are rare and performance
> doesn't seem affected much.

I have seen these, too.  Usually both messages are logged with the same
timestamp.

The problem I'm whining about, however, does not show up in the log at all.
It's a bit like some local locking problem in the NFS code.

> So yesterday I decided to switch to UDP to verify if it's better.
> However, after a certain number of hours, all processes on the client
> locked in tstile wchan/state and I had to reboot the client.
> 
> The problem doesn't seem to be network related, as an ssh
> connection to the server keeps working when this happens, as well as
> HTTP/FTP to the server and outside.  I see no network interface
> diagnostics in dmesg either.  This didn't occur again, but I'll keep
> using UDP a bit for now and see how it goes.

Sounds like my problem.. it usually occurs on my system once or twice
a month.

  -jm