i guess that porteus is installed on NTFS/FAT formatted partition - is it?
otherwise 'changes=/porteus/' cheatcode would never let you fill up the RAM as all files would be saved on the partition where porteus is installed.
Will the changes be persistent if I edit /etc/fstab to mount my home directory on the hard disk?
Porteus is a live linux distro so fstab must be recreated at every boot.
i would recommend you using "magic folders" to pair your /home/guest folder with save.dat (if you have only windows fs around) or folder (if you have at least one linux fs on your hd).
I'm not quite sure how loading into ram works.
copy2ram tells linuxrc (booting script) to copy all modules to RAM first (you can find them in /mnt/live/memory/copy2ram folder). once done booting continues by using modules stored in RAM rather than by using modules placed on your booting media.
this way everything works faster.
copy2ram doesn't force storing everything in RAM.
you can use 'copy2ram' together with 'changes=' cheatcode so porteus will be working faster and your changes remain persistent (as saved on the hard drive)
same applies to 'copy2ram' + "magic folders".
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