Jens could you consider this patch? As far as I can see Barts series has not been merged in any form that would fix my problem and even if it does, requeuing RQF_DONTPREP as head seems on par at worst and a performance improvement at best. -----Original Message----- From: Christian Löhle Sent: Mittwoch, 26. Oktober 2022 09:29 To: axboe@xxxxxxxxx; ulf.hansson@xxxxxxxxxx; linux-mmc@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; 'linux-block@xxxxxxxxxxxxxxx' <linux-block@xxxxxxxxxxxxxxx> Cc: 'Avri Altman' <Avri.Altman@xxxxxxx>; adrian.hunter@xxxxxxxxx; vincent.whitchurch@xxxxxxxx; 'Christian Löhle' <CLoehle@xxxxxxxxxxxxxx> Subject: [PATCH 1/3] block: Requeue req as head if driver touched it In case the driver set RQF_DONTPREP flag, requeue the request as head as it is likely that the backing storage already had a request to an adjacent region, so getting the requeued request out as soon as possible may give us some performance benefit. Signed-off-by: Christian Loehle <cloehle@xxxxxxxxxxxxxx> --- block/blk-mq.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/block/blk-mq.c b/block/blk-mq.c index 33292c01875d..d863c826fb23 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -1429,7 +1429,7 @@ static void blk_mq_requeue_work(struct work_struct *work) * merge. */ if (rq->rq_flags & RQF_DONTPREP) - blk_mq_request_bypass_insert(rq, false, false); + blk_mq_request_bypass_insert(rq, true, false); else blk_mq_sched_insert_request(rq, true, false, false); } -- 2.37.3 Hyperstone GmbH | Reichenaustr. 39a | 78467 Konstanz Managing Director: Dr. Jan Peter Berns. Commercial register of local courts: Freiburg HRB381782