Bug #11847
closed
The nvme cmd completion queue is contentious
Added by Paul Winder over 2 years ago.
Updated over 2 years ago.
Category:
driver - device drivers
Description
When benchmarking for https://www.illumos.org/issues/11827 I discovered the mutex inside the taskq code which guards queue and un-queueing of of tasks is hot and heavily contended.
I propose there is one taskq per completion queue.
The testing results will be posted in 11827
- Precedes Bug #11964: nvme namespace attach and detach ioctls are not safe with concurrent access added
- Status changed from In Progress to Closed
- % Done changed from 70 to 100
git commit 4d95620bc3105916e69c40cff8e2e3d55bd6c4ae
commit 4d95620bc3105916e69c40cff8e2e3d55bd6c4ae
Author: Paul Winder <paul@winders.demon.co.uk>
Date: 2019-11-21T16:46:27.000Z
11827 Increase concurrency through blkdev
11847 The nvme cmd completion queue is contentious
Reviewed by: Robert Mustacchi <rm@fingolfin.org>
Reviewed by: Hans Rosenfeld <rosenfeld@grumpf.hope-2000.org>
Reviewed by: Matthias Scheler <matthias.scheler@wdc.com>
Approved by: Dan McDonald <danmcd@joyent.com>
Also available in: Atom
PDF
Updated by 
Updated by