Booting with the kernel Linux neopili 4.16.0-2-amd64 #1 SMP Debian 4.16.16-2 (2018-06-22) x86_64 GNU/Linux
Writing the same image only takes 25.7s: And these are the avilable schdulers $ cat /sys/block/sdb/queue/scheduler noop deadline [cfq] -- Ricardo Ribalda