I am writing Raspi images on flash card with the following command
dd bs=4M if=image.img of=/dev/sdf conv=fsync status=progress
and it displays progress
5662310400 bytes (5,7 GB, 5,3 GiB) copied, 25 s, 226 MB/s
unfortunately, it does full progres in few seconds, while real writing continues several minutes after this. This is evident because
dd doesn't exit and flash readed LED blinks.
How to make it to display actual progress and/or disable any caching during