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Asked: 2017-03-11 15:42:34 +0800 CST

Where are I/O schedulers set permanently? Kubuntu 20.04.1 64 bit

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I want to use two schedulers since I have a two Disks set for my system due to a separate HOME disk. Meaning I have SDA and SDB

Doing echo noop /sys/block/sda/queue/scheduler says permission denied with SUDO

I tried the suggested solution but it doesn't work anymore

/etc/udev/rules.d/60-schedulers.rules
ACTION=="add|change", KERNEL=="sda", ATTR{queue/scheduler}="noop"
ACTION=="add|change", KERNEL=="nvme0n1", ATTR{queue/scheduler}="noop"
cat /sys/block/nvme0n1/queue/scheduler 
[none] mq-deadline

The setting is to be system-wide

It could be like this

GRUB_CMDLINE_LINUX_DEFAULT="quiet splash elevator:sda=noop elevator:nvme0n1=noop"

Is this the correct line or do I need a comma between the two disk parameters?

kernel

1 Answers

  1. Best Answer

    You should use udev rule for that. 

    /etc/udev/rules.d/60-schedulers.rules

ACTION=="add|change", KERNEL=="sda", ATTR{queue/scheduler}="deadline"
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