Re: [RFC PATCH 0/2] Add mru cache for inode to zone allocation mapping

[hch]

On Wed, Apr 30, 2025 at 08:41:20AM +0000, Hans Holmberg wrote:
> Sending out as an RFC to get comments, specifically about the potential
> mru lock contention when doing the lookup during allocation.

I am a little worried about that.  The MRU cache is implemented right
now rotates the mru list on every lookup under a mru-cache wide lock,
which is bit of a performance nightmare.

I wonder if we can do some form of batched move between the mru buckets
that can reduce the locking and cacheline write impact.

But maybe it's worth to give this a try and work from performance reports
as needed.