Arch Linux

sp4ke

Member

Registered: 2016-05-14

Posts: 6

[solved] upgrade to linux-ck 4.16.13 > "I/O scheduler bfq not found"

Hi all,

I use linux-ck since many months and made upgrades before without problems.

Linux sihil 4.16.13-1-ck-haswell #1 SMP PREEMPT Wed May 30 15:46:19 EDT 2018 x86_64 GNU/Linux

Since the last upgrade which went from ck-haswell 4.14 to 4.16, BFQ scheduler is not working anymore.
I have the following kernel messages with dmesg:

[    0.000000] Command line: root=/dev/sda2 rw initrd=/initramfs-linux-ck-haswell.img intel_iommu=on elevator=bfq vga=824
[    0.000000] Kernel command line: root=/dev/sda2 rw initrd=/initramfs-linux-ck-haswell.img intel_iommu=on elevator=bfq vga=824
[    8.751472] io scheduler bfq registered (default)
[    9.626192] I/O scheduler bfq not found
[    9.626707] I/O scheduler bfq not found
[    9.636067] I/O scheduler bfq not found
[    9.752808] I/O scheduler bfq not found
[    9.753316] I/O scheduler bfq not found
[    9.753793] I/O scheduler bfq not found

And the kernel is compiled with bfq support:

zcat /proc/config.gz   | grep -i bfq                                                                                                                        Thu 16:39
CONFIG_IOSCHED_BFQ=y
CONFIG_BFQ_GROUP_IOSCHED=y

Any idea where this is coming from ?

Last edited by sp4ke (2018-06-04 12:03:25)

Omar007

Member

Registered: 2015-04-09

Posts: 368

Re: [solved] upgrade to linux-ck 4.16.13 > "I/O scheduler bfq not found"

https://wiki.archlinux.org/index.php/Im … _scheduler

loqs

Member

Registered: 2014-03-06

Posts: 17,321

Re: [solved] upgrade to linux-ck 4.16.13 > "I/O scheduler bfq not found"

@Omar007 you did not mention that will switch the system from bfq-sq to bfq or that it no longer works because CK dropped patches supporting the elevator option for bfq / bfq-sq as an alias for bfq and graysky did not reinstate them.
Edit:
https://github.com/ckolivas/linux/pull/7
Edit2:
Corrected that graysky did not drop the patches but did not reinstate them.

Last edited by loqs (2018-06-01 00:32:39)

Omar007

Member

Registered: 2015-04-09

Posts: 368

Re: [solved] upgrade to linux-ck 4.16.13 > "I/O scheduler bfq not found"

I know I didn't. My assumption here was that he is just interested in using BFQ, not specifically the legacy (sq) version of it.
In which case I expect that the note at the link in question is enough information as it explicitly states sq schedulers will not be available in mq mode and that the newer versions of bfq are mq.

If that assumption was wrong, than what loqs says is very much relevant.

Last edited by Omar007 (2018-05-31 21:45:12)

loqs

Member

Registered: 2014-03-06

Posts: 17,321

Re: [solved] upgrade to linux-ck 4.16.13 > "I/O scheduler bfq not found"

I pointed it out as hetfig was at least for 4.14/4.15 advising against MQ/BFQ use has this changed for 4.16?
Edit:
see https://bugs.archlinux.org/task/57496#comment166601

Last edited by loqs (2018-05-31 21:53:55)

graysky

Wiki Maintainer

From: :wq

Registered: 2008-12-01

Posts: 10,597

Website

Re: [solved] upgrade to linux-ck 4.16.13 > "I/O scheduler bfq not found"

I'm just building/packing.  I didn't drop it.

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CPU-optimized Linux-ck packages @ Repo-ck  • AUR packages • Zsh and other configs

loqs

Member

Registered: 2014-03-06

Posts: 17,321

Re: [solved] upgrade to linux-ck 4.16.13 > "I/O scheduler bfq not found"

The result of you not adding it back was the same was it not?
Edit:
Especially as you refused to carry those patches before.  You do add the gcc patch as well.
Edit2:
As we agreed you choose to only build/package I decided to stop supporting linux-ck on the forums.
Edit3:
I apologise for incorrectly attributing the drop to you.

Last edited by loqs (2018-06-01 00:58:19)

sp4ke

Member

Registered: 2016-05-14

Posts: 6

Re: [solved] upgrade to linux-ck 4.16.13 > "I/O scheduler bfq not found"

Thanks @Omar007 and all, I was not aware of those changes. I will update my boot params and mark the thread as solved if it works.

sp4ke

Member

Registered: 2016-05-14

Posts: 6

Re: [solved] upgrade to linux-ck 4.16.13 > "I/O scheduler bfq not found"

Just a quick update, I decided to downgrade the kernel since it's very unstable with windows KVM guests and VFIO. Marking the thread as solved