lkml.org 
[lkml]   [2002]   [Jun]   [12]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
SubjectRe: NFS Client mis-behaviour?
Date
On Tuesday 11 June 2002 18:28, Simon Matthews wrote:

> Other packets were able to make it into and out of the machine: I could
> telnet/ssh/rlogin. The user could not interrupt the process, despite the
> fact that the mount options included "intr".

There is a well known problem with 'intr': if one process is waiting on the
page lock, then there is no provision for interrupting (that's a known
weakness with the MM layer).
Since taking the page lock is usually done by some process that wants to read
from a page, the usual cause of such a hangup is the fact that some other
process is in the middle of an NFS READ. For this reason, if you kill *all*
READ operations (by doing 'killall -9 rpciod) then you can usually recover.
That's something that is only possible for 'root' though...

> My point is that the use of half-duplex may prevent the NFS client from
> sending or receiving (probably sending) some packets. But, since the
> processes that caused the load had stopped doing anything and other packets
> were passing in and out, the NFS client should have been able to recover
> earlier.

As I said, all the client is required to do is to retry (unless it gets
interrupted). I'm not sure what else you mean by 'recover' in the above
sentence.

Cheers,
Trond
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2005-03-22 13:26    [W:0.032 / U:0.736 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site