/etc/udev/rules.d/60-ssd-scheduler.rules is in kubuntu-settings-desktop 1:16.04ubuntu2.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 | ACTION=="add|change", KERNEL=="sd[a-z]", ATTR{queue/rotational}=="1",ATTR{queue/scheduler}="cfq"
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