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Date:   Wed, 25 Sep 2019 16:07:23 -0400
From:   Bruce Fields <bfields@fieldses.org>
To:     Chuck Lever <chuck.lever@oracle.com>
Cc:     Kevin Vasko <kvasko@gmail.com>,
        Linux NFS Mailing List <linux-nfs@vger.kernel.org>
Subject: Re: NFSv4 client locks up on larger writes with Kerberos enabled
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On Wed, Sep 25, 2019 at 11:49:14AM -0700, Chuck Lever wrote:
> Sounds like the NFS server is dropping the connection. With
> GSS enabled, that's usually a sign that the GSS window has
> overflowed.

Would that show up in the rpc statistics on the client somehow?

In that case--I seem to remember there's a way to configure the size of
the client's slot table, maybe lowering that (decreasing the number of
rpc's allowed to be outstanding at a time) would work around the
problem.

Should the client be doing something different to avoid or recover from
overflows of the gss window?

--b.