Re: [PATCH] Fixing soft NFS umount -f, round 3

[Emmanuel Dreyfus <manu%netbsd.org@localhost>]

On Fri, Jul 03, 2015 at 09:59:40AM -0700, Chuck Silvers wrote:
> what's the reason for hardcoding the new timeouts to 2 seconds?
> there's a "-t" mount option to specify a timeout duration.

I used the same delay as for hard mounts. Note this is not the 
connect timeout, this is the time we spend in uninterruptible sleep.
If you look at for instance nfs_receive(), nfs_reconnect() is
called in a loop where retrans count (as given with mount_nfs -x)
is checked. 

What is not tunable is the delay between each reconnect attempt.
We could immagine using the timeout (as given with mount_nfs -t)
but the man page does not say we use this mount option for 
connexion timeouts. Connect failure can be immediate, for instance
when trying a TCP mount on a host which is up but without NFS service
available: once we get a deserved TCP RST, do we want to wait for
timeout before retrying?

-- 
Emmanuel Dreyfus
manu%netbsd.org@localhost