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From:   Chuck Lever III <chuck.lever@oracle.com>
To:     Simon Kirby <sim@hostway.ca>
CC:     Linux NFS Mailing List <linux-nfs@vger.kernel.org>
Subject: Re: Cache flush on file lock
Thread-Topic: Cache flush on file lock
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Date:   Wed, 2 Feb 2022 19:55:47 +0000
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> On Feb 1, 2022, at 8:41 PM, Simon Kirby <sim@hostway.ca> wrote:
>=20
> How far off would we be from write delegations happening here?

We are tracking a "feature request" for write delegation support
in the Linux NFS server:

https://bugzilla.linux-nfs.org/show_bug.cgi?id=3D348

At this point the effort is not resourced. It's not clear how
much benefit it would be.

That said, it seems to me that your use case might benefit if
the Linux NFS server offered a READ delegation for the SQLite
database file even when it is open R/W. It might be appropriate
if the server offered such a delegation when there are no other
clients that have the file open for write or that hold write
delegations.

Patches and performance data are, as always, welcome.


--
Chuck Lever