EMMC write slow

One VIM1 that has been running Ubuntu for years got some weird problems (impossible to execute some sh files for example). Decided to overwrite EMCC with newer image from a sd-card with Krescue.

The write process started normally, but got slower and slower. When a whole hour was spent, the writing speed was already dropped to 240 bytes per second(1). I canceled the process (about 90% of the image was written).

What could this mean, is the EMMC weared out? There was a constant log file writing going on, during the useful worktime. Can I make some tests to find out?

If it is EMMC problem, could the bad areas be somehow excluded?

More than likely yes.

Its best to save log files on the SD or even better SSD on the USB port.

Not really.

Can you run from SD card?

Krescue runs fro SD card.

Seems EMMC it totally broken. Krescue write/read test does not work at all on this.

I will try to shot down logging in the future if there is nothing suspicious going on.

You can run it from SSD on the USB port. That will be much faster than SD card.

booting from USB has never succeeded for me. probably something is missing (uboot?) in the khadas ubuntu images for VIM1.

You will have to start uboot using SD card then switch to USB ssd for the rest.