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charset=us-ascii Content-Disposition: inline On Thu, Oct 05, 2023 at 02:31:03AM -0700, Yosry Ahmed wrote: > I am not really sure what you mean here. My "vision" is to treat WORKINGSET_ entries as events. That would mean implementing per-node tracking for vm_event_item (costlier?). That would mean node_stat_item and vm_event_item being effectively equal, so they could be merged in one. That would be situation to come up with new classification based on use cases (e.g. precision/timeliness requirements, state vs change semantics). (Do not take this as blocker of the patch 1/2, I rather used the opportunity to discuss a greater possible cleanup.) > We don't track things like OOM_KILL and DROP_PAGECACHE per memcg as > far as I can tell. Ah, good. (I forgot only subset of entries is relevant for memcgs.) > This will mean that WORKINGSET_* state will become more stale. We will > need 4096 as many updates as today to get a flush. These are used by > internal flushers (reclaim), and are exposed to userspace. I am not > sure we want to do that. snapshot_refaults() doesn't seem to follow after flush and workigset_refault()'s flush doesn't seem to preceed readers Is the flush misplaced or have I overlooked something? (If the former, it seems to work good enough even with the current flushing heuristics :-)) Michal --tpu3njifk2lp5cu6 Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iHUEABYKAB0WIQQpEWyjXuwGT2dDBqAGvrMr/1gcjgUCZR7knwAKCRAGvrMr/1gc jmuCAQDLOZF2u7hvOxa6XliRfkYY1Be/D0QEHOZynh1+OxsDKQD/aGTjJFAWvb5D qEcqxkg0fd9+iYdI1PSQdU3ICEFERAs= =t1Ez -----END PGP SIGNATURE----- --tpu3njifk2lp5cu6--