On Wed, Dec 12, 2018 at 04:30:20PM -0700, stan wrote:
On Wed, 12 Dec 2018 14:41:37 -0700
stan <stanl-fedorauser(a)vfemail.net> wrote:
> On Wed, 12 Dec 2018 16:07:49 -0500
> Jeff Moyer <jmoyer(a)redhat.com> wrote:
>
> Thanks for your insight. Doesn't look good for my use of BFQ.
>
> > Note that you can change the current I/O scheduler for any block
> > device by echo-ing into /sys/block/<dev>/queue/scheduler. Cat-ing
> > that file will give you the list of available schedulers.
>
> That's part of the problem. BFQ doesn't appear in the list of
> available schedulers. When I cat that location for my disks, I see
> [noop]. Since CFQ does appear there if it is compiled into the
> kernel, I'll have to look into what is done for CFQ and see how hard
> it would be to patch the kernel to repeat that behavior for BFQ.
Enabled deadline and cfq again, but still no bfq available.
$ cat /sys/block/sda/queue/scheduler
noop deadline [cfq]
Those are single-queue scheduler. Multiqueue uses different
schedulers: bfq, kyber, mq-deadline. MQ schedulers won't appear on
single-queue devices even if you modprobe such schedulers.
You probably need “scsi_mod.use_blk_mq=y dm_mod.use_blk_mq=y” kernel
commandline options, although I think those are default in recent
kernels.
--
Tomasz Torcz 72->| 80->|
xmpp: zdzichubg(a)chrome.pl 72->| 80->|