deadline

English Install/Boot/Login
1

When I start Leap 15 I see “I / O discard scheduler not found” a few lines just in front of the login screen.
Has the discard option been taken from Leap 15 or do I sometimes miss a package?

Gerrit Jan

2

I am a sleeper …
It is not discard but deadline!

When I start Leap 15 I see “I / O deadline scheduler not found” a few lines just in front of the login screen.

ps. a moderator can change the subject to Deadline

Sorry Gerrit Jan :Z

3

Hi
What do you see from the following output (assuming disk is sda);


cat /sys/block/sda/queue/scheduler

dmesg |grep scheduler

Is the hard drive a rotating one or SSD?

4

yes it’s a ssd

linux-ar8p:~ # cat /sys/block/sda/queue/scheduler
noop deadline [cfq] 
linux-ar8p:~ # dmesg |grep scheduler
    0.937334] io scheduler noop registered
    0.937334] io scheduler deadline registered
    0.937339] io scheduler cfq registered
    0.937339] io scheduler mq-deadline registered
    0.937340] io scheduler kyber registered
    0.937344] io scheduler bfq registered
    1.731289] I/O scheduler deadline. not found
    1.732168] I/O scheduler deadline. not found
    1.735034] I/O scheduler deadline. not found
    1.735245] I/O scheduler deadline. not found
    1.737486] I/O scheduler deadline. not found
    1.749861] I/O scheduler deadline. not found
5

Hi
Strange that the udev rule is not detecting it as an ssd and setting to deadline.

If you look in /usr/lib/udev/rules.d directory is there a ssd scheduler present?


ll /usr/lib/udev/rules.d/*ssd*

It should be part of udev, but maybe this is a new SSD (or nvme device)?

6

It has extra dot at the end. You need to find out where it comes from; it seems to be specific to your system.

7

Hi
Must be a manual edit of a file…?

8 
linux-ar8p:~ # ll /usr/lib/udev/rules.d/*ssd*
-rw-r--r-- 1 root root 329 May 14 20:08 /usr/lib/udev/rules.d/60-ssd-scheduler.rules

No it’s a old ssd, use a long time now. M4-CT128M4SSD2
With tumbleweed no problems.

9

found it!
it was the bootloader kernel parameters, there was a point behind elevator=deadline.
moreover, the whole line was there twice.
strange, no idea how that happens?
Well, it is solved.

Thanks for contributing,
Gerrit Jan

10

On Thu 07 Jun 2018 09:36:03 AM CDT, GJElde wrote:

found it!
it was the bootloader kernel parameters, there was a point behind
elevator=deadline.
moreover, the whole line was there twice.
strange, no idea how that happens?
Well, it is solved.

Thanks for contributing,
Gerrit Jan

Hi
The grub command line option should not be needed, the ssd udev rule
should set it.

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11

thanks for the tip, I will change it.

Gerrit Jan