Confirm current configuration.

$ cat /sys/block/sda/queue/scheduler 
noop deadline [cfq] 

To change default value, edit /etc/default/grub

GRUB_CMDLINE_LINUX_DEFAULT="elevator=noop"

Reboot.

• https://qiita.com/yoichiwo7/items/9ffbae15d6bc11ff419b

• https://fredrik.wendt.se/2014/07/06/virtualbox-with-poor-io-performance/