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Message-ID: <e7c547f0ef877c3e1ae7b22ff738990f16c498c6.camel@redhat.com>
Subject: Re: [PATCH/RFC] sunrpc: constant-time code to wake idle thread
From:   Jeff Layton <jlayton@redhat.com>
To:     Chuck Lever III <chuck.lever@oracle.com>,
        Neil Brown <neilb@suse.de>
Cc:     Chuck Lever <cel@kernel.org>,
        Linux NFS Mailing List <linux-nfs@vger.kernel.org>,
        "lorenzo@kernel.org" <lorenzo@kernel.org>,
        Dave Chinner <david@fromorbit.com>
Date:   Tue, 11 Jul 2023 07:50:00 -0400
In-Reply-To: <B94C13E5-D84F-4BF7-A559-4E701B0AFA6D@oracle.com>
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On Mon, 2023-07-10 at 22:43 +0000, Chuck Lever III wrote:
>=20
> > On Jul 10, 2023, at 6:30 PM, Jeff Layton <jlayton@redhat.com> wrote:
> >=20
> > On Tue, 2023-07-11 at 08:18 +1000, NeilBrown wrote:
> > > On Tue, 11 Jul 2023, Chuck Lever wrote:
> > > >=20
> > > > Actually... Lorenzo reminded me that we need to retain a mechanism
> > > > that can iterate through all the threads in a pool. The xarray
> > > > replaces the "all_threads" list in this regard.
> > > >=20
> > >=20
> > > For what purpose?
> > >=20
> >=20
> > He's working on a project to add a rpc status procfile which shows in-
> > flight requests:
> >=20
> >    https://bugzilla.linux-nfs.org/show_bug.cgi?id=3D366
>=20
> Essentially, we want a lightweight mechanism for detecting
> unresponsive nfsd threads.
>=20

...and personally, it would also be nice to have a "nfstop" program or
something that could repeatedly poll this file and display information
about active nfsd threads. I could also see this being useful for admins
who want quick visibility into nfsd's activity, without having to sniff
traffic.
--=20
Jeff Layton <jlayton@redhat.com>