[dm-devel] [RFC PATCH 0/4] dm mpath: vastly improve blk-mq IO performance

[Mike Snitzer]

On Fri, Apr 08 2016 at  7:42am -0400,
Johannes Thumshirn <jthumshirn at suse.de> wrote:

> Ladies and Gentlemen,
> To show off some numbers from our testing:
> 
> All tests are performed against the cache of the Array, not the disks as we 
> wanted to test the Linux stack not the Disk Array.
> 
> All single queue tests have been performed with the deadline I/O Scheduler.
> 
> Comments welcome, have fun reading :-)

Any chance you collected performance results from DM MQ on this same
testbed without any variant of my lockless patches?  The DM SQ results
aren't too interesting a reference point.  Seeing how much better
lockless DM MQ (multipath) is than the old m->lock heacy code (still in
4.6) would be more interesting.

Not a big deal if you don't have it.. but figured I'd check to see.

And thanks for the numbers you've provided.
Mike