On Tue, May 2, 2017 at 10:07 AM, Sedat Dilek [off-list ref] wrote:

On Tue, May 2, 2017 at 10:00 AM, Markus Trippelsdorf
[off-list ref] wrote:

quoted

On 2017.05.02 at 09:54 +0200, Sedat Dilek wrote:

quoted

Hi,

I want to play with BFQ.

My base is block-next as of 28-Apr-2017.

First I looked through the Kconfigs.
What is a good setting?
Built as module?

How can I switch the IO-scheduler - real-time?

Not sure if the attached patches make sense (right now).

No, it doesn't make sense at all.
BFQ is a mq scheduler. To use it you should enable
SCSI_MQ_DEFAULT. And then you can switch schedulers like:

 echo "kyber" > /sys/block/sda/queue/scheduler
 echo "bfq" > /sys/block/sdb/queue/scheduler

Great, I got these informations before starting a kernel-build.

So, I have now...

$ ./scripts/diffconfig /boot/config-4.11.0-1-iniza-amd64 .config
-BLK_DEV_HD n
 SCSI_MQ_DEFAULT n -> y
+BFQ_GROUP_IOSCHED y
+BLK_DEV_THROTTLING_LOW n
+IOSCHED_BFQ y
+MQ_IOSCHED_KYBER y

Thanks, Markus.

This worked...

# cat /sys/block/sda/queue/scheduler
[mq-deadline] kyber bfq none

# echo "bfq" > /sys/block/sda/queue/scheduler

# cat /sys/block/sda/queue/scheduler
mq-deadline kyber [bfq] none

- sed@ -