From: Christoph Hellwig <hch@lst.de>
To: Chuck Lever <cel@kernel.org>
Cc: Sagi Grimberg <sagi@grimberg.me>, Christoph Hellwig <hch@lst.de>,
Trond Myklebust <trondmy@kernel.org>,
Anna Schumaker <anna@kernel.org>,
linux-nfs@vger.kernel.org
Subject: Re: add a LRU for delegations
Date: Thu, 8 Jan 2026 16:35:46 +0100 [thread overview]
Message-ID: <20260108153546.GA7623@lst.de> (raw)
In-Reply-To: <45ba87f3-2322-424b-95b1-9129a2537545@app.fastmail.com>
On Thu, Jan 08, 2026 at 09:34:28AM -0500, Chuck Lever wrote:
> The server and client have orthogonal interests here, IMO.
>
> The server is concerned with resource utilization -- memory consumed,
> slots in tables, and so on -- that other active clients might benefit
> from having freed. The server doesn't really care which delegations
> are returned.
>
> A client wants to keep delegation state that applications are using,
> and it knows best which ones those are. It can identify specific
> delegations that are not being actively used and return those.
Yes. A good way to deal with that is implementing RECALLY_ANY as I
mentioned, which with these changes could reclaim off the end of the LRU.
But as this series is a big change already, and doing fine grained
recalls is another huge one I'd rather wait a bit before going there.
next prev parent reply other threads:[~2026-01-08 15:35 UTC|newest]
Thread overview: 41+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-01-07 7:26 add a LRU for delegations Christoph Hellwig
2026-01-07 7:26 ` [PATCH 01/24] NFS: remove __nfs_client_for_each_server Christoph Hellwig
2026-01-07 7:26 ` [PATCH 02/24] NFS: remove nfs_client_mark_return_unused_delegation_types Christoph Hellwig
2026-01-07 7:26 ` [PATCH 03/24] NFS: remove nfs_client_mark_return_all_delegations Christoph Hellwig
2026-01-07 7:26 ` [PATCH 04/24] NFS: remove the NULL inode check in nfs4_inode_return_delegation_on_close Christoph Hellwig
2026-01-07 7:26 ` [PATCH 05/24] NFS: remove nfs_inode_detach_delegation Christoph Hellwig
2026-01-07 7:26 ` [PATCH 06/24] NFS: remove nfs_start_delegation_return Christoph Hellwig
2026-01-07 7:26 ` [PATCH 07/24] NFS: assert rcu_read_lock is held in nfs_start_delegation_return_locked Christoph Hellwig
2026-01-07 7:26 ` [PATCH 08/24] NFS: drop the _locked postfix from nfs_start_delegation_return Christoph Hellwig
2026-01-07 7:27 ` [PATCH 09/24] NFS: remove NFS_DELEGATION_INODE_FREEING Christoph Hellwig
2026-01-07 7:27 ` [PATCH 10/24] NFS: open code nfs_delegation_need_return Christoph Hellwig
2026-01-07 7:27 ` [PATCH 11/24] NFS: remove nfs_free_delegation Christoph Hellwig
2026-01-07 7:27 ` [PATCH 12/24] NFS: rewrite nfs_delegations_present in terms of nr_active_delegations Christoph Hellwig
2026-01-07 7:27 ` [PATCH 13/24] NFS: move delegation lookup into can_open_delegated Christoph Hellwig
2026-01-07 7:27 ` [PATCH 14/24] NFS: return bool from nfs_detach_delegation{,_locked} Christoph Hellwig
2026-01-07 7:27 ` [PATCH 15/24] NFS: move the deleg_cur check out of nfs_detach_delegation_locked Christoph Hellwig
2026-01-07 7:27 ` [PATCH 16/24] NFS: simplify the detached delegation check in update_open_stateid Christoph Hellwig
2026-01-07 7:27 ` [PATCH 17/24] NFS: take a delegation reference in nfs4_get_valid_delegation Christoph Hellwig
2026-01-07 7:27 ` [PATCH 18/24] NFS: don't consume a delegation reference in nfs_end_delegation_return Christoph Hellwig
2026-01-07 7:27 ` [PATCH 19/24] NFS: use refcount_inc_not_zero nfs_start_delegation_return Christoph Hellwig
2026-01-07 7:27 ` [PATCH 20/24] NFS: use a local RCU critical section in nfs_start_delegation_return Christoph Hellwig
2026-01-07 7:27 ` [PATCH 21/24] NFS: reformat nfs_mark_delegation_revoked Christoph Hellwig
2026-01-07 7:27 ` [PATCH 22/24] NFS: add a separate delegation return list Christoph Hellwig
2026-01-25 13:30 ` Chris Mason
2026-01-26 6:06 ` Christoph Hellwig
2026-01-07 7:27 ` [PATCH 23/24] NFS: return delegations from the end of a LRU when over the watermark Christoph Hellwig
2026-01-07 7:27 ` [PATCH 24/24] NFS: make nfs_mark_return_unreferenced_delegations less aggressive Christoph Hellwig
2026-01-07 15:18 ` add a LRU for delegations Chuck Lever
2026-01-07 16:22 ` Christoph Hellwig
2026-01-07 19:22 ` Sagi Grimberg
2026-01-08 13:46 ` Christoph Hellwig
2026-01-09 0:13 ` Sagi Grimberg
2026-01-08 14:34 ` Chuck Lever
2026-01-08 15:35 ` Christoph Hellwig [this message]
2026-01-09 0:30 ` Sagi Grimberg
2026-01-09 1:07 ` Trond Myklebust
2026-01-11 7:46 ` Sagi Grimberg
2026-01-15 16:24 ` Christoph Hellwig
2026-01-21 20:42 ` Anna Schumaker
-- strict thread matches above, loose matches on Subject: below --
2025-12-18 5:56 Christoph Hellwig
2025-12-18 5:50 Christoph Hellwig
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