Re: FreeBSD 13.2 NFS client mount hangs

From: Rick Macklem <rick.macklem_at_gmail.com>
Date: Mon, 09 Oct 2023 05:34:27 UTC
On Sun, Oct 8, 2023 at 8:32 PM J David <j.david.lists@gmail.com> wrote:
>
> On Sat, Oct 7, 2023 at 3:08 PM Rick Macklem <rick.macklem@gmail.com> wrote:
> > One thing you could try is running the nfscbd(8) daemon.
> > [...]
> > Maybe this server will be happier with the callback path working?
>
> Unfortunately, this avenue of inquiry proved unfruitful. Due to the
> warning on the man page, I removed oneopenown before enabling nfscbd.
> Over the course of the next few hours, that drove system load and CPU
> usage through the roof, with LocalOwn and LocalOpen continually
> increasing into the tens of millions. That must be the nfscbd version
> of the OpenOwner problem.
LocalOwn and LocalOpens indicate that the server did start issuing
delegations. I guess you do need to not run the nfscbd(8).

It is odd that the number of opens would increase dramatically.
All I can think of is that you have an environment where the
same file(s) get open'd by multiple processes.
A NFSv4 close cannot occur until a file has no open references.
--> No process has the file open.
The "oneopenown" option at least ensures that there is a single
open owner (without it, each process is a separate open owner).

rick

>
> Thanks!