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| author | smh <smh@FreeBSD.org> | 2013-03-29 22:58:15 +0000 |
|---|---|---|
| committer | smh <smh@FreeBSD.org> | 2013-03-29 22:58:15 +0000 |
| commit | fc36a232b91d6ddc6b7d1429049d052764181391 (patch) | |
| tree | bb7d2f8108f86f3417b00d4bf9c025cf6f66ae71 /sys/cam/ata | |
| parent | 35fe5219abd995454f3d1279b840072f555159c3 (diff) | |
| download | FreeBSD-src-fc36a232b91d6ddc6b7d1429049d052764181391.zip FreeBSD-src-fc36a232b91d6ddc6b7d1429049d052764181391.tar.gz | |
Adds the ability to enable / disable sorting of BIO requests queued within
CAM. This can significantly improve performance particularly for SSDs
which don't suffer from seek latencies.
The sysctl / tunable kern.cam.sort_io_queues provides the systems default
setting where:-
0 = queued BIOs are NOT sorted
1 = queued BIOs are sorted (default)
Each device gets its own sysctl kern.cam.<type>.<id>.sort_io_queue
Valid values are:-
-1 = use system default (default)
0 = queued BIOs are NOT sorted
1 = queued BIOs are sorted
Note: Additional patch will look to add automatic use of none sorted queues
for none rotating media e.g. SSD's
Reviewed by: scottl
Approved by: pjd (mentor)
MFC after: 2 weeks
Diffstat (limited to 'sys/cam/ata')
| -rw-r--r-- | sys/cam/ata/ata_da.c | 23 |
1 files changed, 19 insertions, 4 deletions
diff --git a/sys/cam/ata/ata_da.c b/sys/cam/ata/ata_da.c index 159091b..1457133 100644 --- a/sys/cam/ata/ata_da.c +++ b/sys/cam/ata/ata_da.c @@ -130,6 +130,7 @@ struct ada_softc { ada_state state; ada_flags flags; ada_quirks quirks; + int sort_io_queue; int ordered_tag_count; int outstanding_cmds; int trim_max_ranges; @@ -449,6 +450,8 @@ static void adaresume(void *arg); softc->read_ahead : ada_read_ahead) #define ADA_WC (softc->write_cache >= 0 ? \ softc->write_cache : ada_write_cache) +#define ADA_SIO (softc->sort_io_queue >= 0 ? \ + softc->sort_io_queue : cam_sort_io_queues) /* * Most platforms map firmware geometry to actual, but some don't. If @@ -670,10 +673,17 @@ adastrategy(struct bio *bp) * Place it in the queue of disk activities for this disk */ if (bp->bio_cmd == BIO_DELETE && - (softc->flags & ADA_FLAG_CAN_TRIM)) - bioq_disksort(&softc->trim_queue, bp); - else - bioq_disksort(&softc->bio_queue, bp); + (softc->flags & ADA_FLAG_CAN_TRIM)) { + if (ADA_SIO) + bioq_disksort(&softc->trim_queue, bp); + else + bioq_insert_tail(&softc->trim_queue, bp); + } else { + if (ADA_SIO) + bioq_disksort(&softc->bio_queue, bp); + else + bioq_insert_tail(&softc->bio_queue, bp); + } /* * Schedule ourselves for performing the work. @@ -999,6 +1009,10 @@ adasysctlinit(void *context, int pending) SYSCTL_ADD_INT(&softc->sysctl_ctx, SYSCTL_CHILDREN(softc->sysctl_tree), OID_AUTO, "write_cache", CTLFLAG_RW | CTLFLAG_MPSAFE, &softc->write_cache, 0, "Enable disk write cache."); + SYSCTL_ADD_INT(&softc->sysctl_ctx, SYSCTL_CHILDREN(softc->sysctl_tree), + OID_AUTO, "sort_io_queue", CTLFLAG_RW | CTLFLAG_MPSAFE, + &softc->sort_io_queue, 0, + "Sort IO queue to try and optimise disk access patterns"); #ifdef ADA_TEST_FAILURE /* * Add a 'door bell' sysctl which allows one to set it from userland @@ -1134,6 +1148,7 @@ adaregister(struct cam_periph *periph, void *arg) snprintf(announce_buf, sizeof(announce_buf), "kern.cam.ada.%d.write_cache", periph->unit_number); TUNABLE_INT_FETCH(announce_buf, &softc->write_cache); + softc->sort_io_queue = -1; adagetparams(periph, cgd); softc->disk = disk_alloc(); softc->disk->d_devstat = devstat_new_entry(periph->periph_name, |
