It seems that the ramsize boot parameter is not respected in minix3
I was trying to streach a floppy image as suggested in "Making a RAM
Disk Larger than 8 Megabytes" and finally found out that dd if=/dev/ram
of=/dev/null bs=1k shows 1440 :/

Because using the ramdisk command clears the ramdisk contents, I solved
that using rootdev=fd0 and then ramdisk nnnnnnnnn; dd if=/dev/fd0
of=/dev/ram; newroot /dev/ram.

Perhaps that might be noted on the "8 Megabytes" page? I guess that
mkfs -t /dev/fd0 65535 should be changed to mkfs -t /dev/fd0 65535 -i
8192 or whatever as an example - the default inode quantity doesn't fit
in the first 1440 kbyte blocks rendering the floppy designated for
ramdisk useles (and failing silently while copying files/creating
directories). The inode discussion is of course mentioned below but an
example should be a working start, shouldn't it?

I also didn't change the number of zones (changing it to suggested 1440
appeared to give "strange" free disk space amounts) and it seems to work
as expected.