Decrease ramdisk (tmpfs) to increase available RAM memory

I am looking to increase the amount of RAM by about 100K and was wondering if I could ‘steal’ some from ramdisk.

I see several tmpfs when running mount command but don’t see setting up of tmps in /etc/fstab so am guessing this is done elsewhere.

Firstly is this possible and/or wise to do and secondly any suggestions on where to find creation of ram disks on startup.