On Mon, Apr 30, 2018 at 09:32:50AM -0600, Jens Axboe wrote: > We recently had a pretty severe perf regression with the XFS async > discard. This small series add a SYNC issue discard flag, and also > limits the chain size for sync discards. Patch 2 adds support for > reverting XFS back to doign sync discards. Please explain the hardware and workload that you see this with. Also given that it is a hardware limitation a quirk limiting the size of discard requests and/or number of outstanding discards would be more useful than falling back to a broken mode of issueing block commands.
