Comment 5 for bug 317161

"Also, does adding the option in a remount actually have any effect?"

yes,

iuri@cego:~$ free
             total used free shared buffers cached
Mem: 1285120 1249400 35720 0 205400 422532
-/+ buffers/cache: 621468 663652
Swap: 2441872 12608 2429264

iuri@cego:~$ df -h /dev/
Filesystem Size Used Avail Use% Mounted on
udev 628M 2.9M 625M 1% /dev

iuri@cego:~$ sudo mount /dev/ -o remount,size=8M
[sudo] password for iuri:

iuri@cego:~$ df -h /dev/
Filesystem Size Used Avail Use% Mounted on
udev 8.0M 2.9M 5.2M 36% /dev
iuri@cego:~$