For file systems running on an SSD or in a virtualized environment, use the noop scheduler. On some systems, such as RHEL 8.1+, this is called none. For all other systems, use the deadline scheduler.

  1. To determine which scheduler is configured on your system, run the following command.
    $ cat /sys/block/<block-device>/queue/scheduler
  2. To change the scheduler on a running system, run the following command.
    $ echo '<scheduler name>' > /sys/block/<block-device>/queue/scheduler

    In the following example, the system is updated to use the deadline scheduler.

    $ echo 'deadline' > /sys/block/sda/queue/scheduler
  3. To enable the change, restart the system.

    The procedure for configuring a scheduler to use at startup depends on the version of Linux. For the correct way to configure this setting, see the system documentation.