[PATCH][DISCO] UBUNTU: SAUCE: config: enable mq-deadline as default for multi-queue block I/O

Colin King colin.king at canonical.com
Tue Dec 11 13:06:51 UTC 2018

From: Colin Ian King <colin.king at canonical.com>

There is compelling data showing that enabling the mq-deadline block I/O
scheduler as default for multi-queue devices is a sensible default. It
performs well across a range of I/O scenarios and is applicable for
various device drivers (null_blk, virtio-blk, mtip32xx, scsi_mq, NVMe,
rbd, ubiblock, loop, dm and dm-mpath).

For the moment, users who want to disable mq I/O schduling can diable
this with a kernel boot paremater, for example for SCSI block devices
use: scsi_mod.use_blk_mq=0.  This will fall back to the I/O scheduler
defaults used in releases prior to 4.20 kernels in Ubuntu.

For non-multiqueue devices we currently fall back to the current
Ubuntu default of cfq, although at a later date  I'd like to change
this too to deadline once the mq-deadline defaults have settled in.

Signed-off-by: Colin Ian King <colin.king at canonical.com>
 debian.master/config/config.common.ubuntu | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/debian.master/config/config.common.ubuntu b/debian.master/config/config.common.ubuntu
index 1d21a87..8c1015e 100644
--- a/debian.master/config/config.common.ubuntu
+++ b/debian.master/config/config.common.ubuntu
@@ -5730,7 +5730,7 @@ CONFIG_MPROFILE_KERNEL=y
 # CONFIG_MPSC is not set

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