Usually you would use the `dd` command to copy a disk image to an SD card and then tune the `bs` parameter for speed. But it might be that `cat` is faster, simply like this:
cat <disk.img> >/dev/<device>
Let's see if this is true.
SD card writing tests with a 30G image:
$ time dd if=rpi_debian.img of=/dev/sde bs=1M real 32m23.274s $ time dd if=rpi_debian.img of=/dev/sde bs=10M real 32m16.737s $ time dd if=rpi_debian.img of=/dev/sde bs=100M real 32m17.373s $ time cat rpi_debian.img >/dev/sde real 11m56.924s
SD card reading tests with a 30G card:
$ time dd if=/dev/sde of=rpi.img bs=1M $ time dd if=/dev/sde of=rpi.img bs=10M real 27m9.273s $ time dd if=/dev/sde of=rpi.img bs=100M real 27m22.742s # time cat /dev/sde >rpi.img real 26m1.219s
`cat` clearly performs better. `dd`, you have served me well, but it's time to say good bye.
Created: 6/Jan/2024
Modified: 21/Jan/2024