diff options
| author | Damien Le Moal <dlemoal@kernel.org> | 2026-02-27 22:19:50 +0900 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2026-03-09 14:30:00 -0600 |
| commit | 3d9782f62fb7c2c9ec3020c579425d634559d600 (patch) | |
| tree | 77b6af2413b51afa5fb808bec7305b8b82f16689 /block | |
| parent | 1365b6904fd050bf22ab9f3df375a396de5837a1 (diff) | |
| download | ath-3d9782f62fb7c2c9ec3020c579425d634559d600.tar.gz | |
block: default to QD=1 writes for blk-mq rotational zoned devices
For blk-mq rotational zoned block devices (e.g. SMR HDDs), default to
having zone write plugging limit write operations to a maximum queue
depth of 1 for all zones. This significantly reduce write seek overhead
and improves SMR HDD write throughput.
For remotely connected disks with a very high network latency this
features might not be useful. However, remotely connected zoned devices
are rare at the moment, and we cannot know the round trip latency to
pick a good default for network attached devices. System administrators
can however disable this feature in that case.
For BIO based (non blk-mq) rotational zoned block devices, the device
driver (e.g. a DM target driver) can directly set an appropriate
default.
Signed-off-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'block')
| -rw-r--r-- | block/blk-sysfs.c | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/block/blk-sysfs.c b/block/blk-sysfs.c index ca8033e6d6990..878b8a4b55bb6 100644 --- a/block/blk-sysfs.c +++ b/block/blk-sysfs.c @@ -967,6 +967,14 @@ int blk_register_queue(struct gendisk *disk) blk_mq_debugfs_register(q); blk_debugfs_unlock(q, memflags); + /* + * For blk-mq rotational zoned devices, default to using QD=1 + * writes. For non-mq rotational zoned devices, the device driver can + * set an appropriate default. + */ + if (queue_is_mq(q) && blk_queue_rot(q) && blk_queue_is_zoned(q)) + blk_queue_flag_set(QUEUE_FLAG_ZONED_QD1_WRITES, q); + ret = disk_register_independent_access_ranges(disk); if (ret) goto out_debugfs_remove; |