diff options
| author | Mike Snitzer <snitzer@redhat.com> | 2015-03-08 00:51:47 -0500 |
|---|---|---|
| committer | Mike Snitzer <snitzer@redhat.com> | 2015-04-15 12:10:16 -0400 |
| commit | bfebd1cdb497a57757c83f5fbf1a29931591e2a4 (patch) | |
| tree | c4ca9675ad22a45eb6e36b130db0d65d574dd2b3 /include | |
| parent | 0ce65797a77ee780f62909d3128bf08b9735718b (diff) | |
dm: add full blk-mq support to request-based DM
Commit e5863d9ad ("dm: allocate requests in target when stacking on
blk-mq devices") served as the first step toward fully utilizing blk-mq
in request-based DM -- it enabled stacking an old-style (request_fn)
request_queue ontop of the underlying blk-mq device(s). That first step
didn't improve performance of DM multipath ontop of fast blk-mq devices
(e.g. NVMe) because the top-level old-style request_queue was severely
limited by the queue_lock.
The second step offered here enables stacking a blk-mq request_queue
ontop of the underlying blk-mq device(s). This unlocks significant
performance gains on fast blk-mq devices, Keith Busch tested on his NVMe
testbed and offered this really positive news:
"Just providing a performance update. All my fio tests are getting
roughly equal performance whether accessed through the raw block
device or the multipath device mapper (~470k IOPS). I could only push
~20% of the raw iops through dm before this conversion, so this latest
tree is looking really solid from a performance standpoint."
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Tested-by: Keith Busch <keith.busch@intel.com>
Diffstat (limited to 'include')
| -rw-r--r-- | include/uapi/linux/dm-ioctl.h | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/include/uapi/linux/dm-ioctl.h b/include/uapi/linux/dm-ioctl.h index 889f3a5b7b18..eac8c3641f39 100644 --- a/include/uapi/linux/dm-ioctl.h +++ b/include/uapi/linux/dm-ioctl.h @@ -267,9 +267,9 @@ enum { #define DM_DEV_SET_GEOMETRY _IOWR(DM_IOCTL, DM_DEV_SET_GEOMETRY_CMD, struct dm_ioctl) #define DM_VERSION_MAJOR 4 -#define DM_VERSION_MINOR 30 +#define DM_VERSION_MINOR 31 #define DM_VERSION_PATCHLEVEL 0 -#define DM_VERSION_EXTRA "-ioctl (2014-12-22)" +#define DM_VERSION_EXTRA "-ioctl (2015-3-12)" /* Status bits */ #define DM_READONLY_FLAG (1 << 0) /* In/Out */ |