tree 33da96fa4f1949af33492299930491f2ee797c9a
parent 56392d2f40aac4b520fc50bc356f40e07f7e1c7d
author Lars Ellenberg <lars.ellenberg@linbit.com> 1363713409 +0100
committer Jens Axboe <axboe@kernel.dk> 1363997640 -0600

drbd: drbd_al_being_io: short circuit to reduce latency

A request hitting an already "hot" extent should proceed right away,
even if some other requests need to wait for pending transactions.

Without that short-circuit, several simultaneous make_request contexts
race for committing the transaction, possibly penalizing the innocent.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>