Sizes of /dev /dev/shm /lib/init/rw
Few questions about all of these. To make things easier, there's 512MB RAM and a 1.5GB swap drive in this box.
/dev has a capacity of 10M, which seems to high to me, since I've never seen more than 870K used. I know this can be adjusted somewhere, as I stumbled across a number somewhere one day that said something along the lines of udev=10M, but I can't find it anymore. Based on that option, is that 10M allocated out of RAM, Swap, or just on the HDD?
/dev/shm is shared memory space from what I've been able to find. Right now it has a capacity of 248M, and 0 is used. As with /dev, where is this space allocated? Is there a point in making it larger/smaller?
/lib/init/rw has the same size as /dev/shm, but from what I understand is a RAM disk used during boot.
I've also read that tmpfs RAM disks are rather efficient when empty, but I would still like to decrease the size in case some program goes wrong and fills up /dev/shm. I just don't see a need for so much unused space?
What are all the advantages/disadvantages & procedures for this?