On 6/16/2017 6:17 AM, Andreas Henriksson wrote: > As can be seen in the while loop at: > http://sources.debian.net/src/util-linux/2.29.2-1/sys-utils/fstrim.c/#L205 > ... the code tries to iterate over all mounted filesystems and then > skip over ones that should not be considered (pseudo filesystems, > not having discard support, etc).
My guess would be that ext2 doesn't support discard... or at least fstrim thinks that is so. Whether your kernel has the real ext2 driver or is mounting it with the ext4 driver may make a difference.
