Puppy Linux Discussion Forum

This computer is running Fatdog64-812. I thought I would change the save interval so that it would only save what was in RAM to the save folder on command.
Using the control panel I went to System and started "Fatdog64 Event Manager". Hovering over the RAM save interval brings up the following text

When running with Ram layer, Fatdog will periodically save
the RAM layer contents to the persistent savefile.

Specify the interval between saves here, in minutes. If you
enter zero (0) here, periodic saving is disabled and nothing
will be saved unless you click the "Save RAM Layer" button on
the desktop.

Setting takes effect immediately.

Entering 0 in this box, saving and exiting the event manager does not produce a "Save RAM Layer" button nor does one appear following a reboot although checking the event manager shows that the save interval stays at 0.
What am I missing or doing wrong?

You have to tell fatdog that it should run in ram by kernel parameters. In GRUB's menu.lst file, the line looks like this.

kernel /fatdog812/vmlinuz waitdev 0:0 rootfstype=ramfs savefile=ram:device:sda4:fatdog812/fd64save

... savefile=ram: .... is the important part that lets fatdog run in ram and only save in intervals. You automatically get the desktop icon and can set save interval to zero to only allow manual saves.

Many thanks, chiron, your post contained the solution. (in my case the savefile parameter uses uuid rather than device as my "Hard Drive" is an nvme SSD)
cheers,
Ken

I like to setup my Fatdog to boot/save using multi-session style, a old approach where you could boot from and save back to CD, but where the save files can be on HDD (as I use it).

title Fatdog 812 Final
root (hd0,0)
kernel /FATDOG812-FINAL/vmlinuz basesfs=ram:uuid:xxx:/FATDOG812-FINAL/fd64.sfs savefile=direct:multi:uuid:xxx:/FATDOG812-FINAL/: 
initrd /FATDOG812-FINAL/initrd

There's a save icon on the desktop and if you set the save interval to zero in EventManager then it only saves whenever that save icon is clicked - that creates an additional multi....save.sfs file of those changes - so you have a audit trail of all prior saves in a bunch of sfs files.

Update/change something and run a save, reboot and decide you don't like it with those updates/changes, then removing the last multi...save.sfs file has those changes undone.

I periodically merge those multi...sfs files into the main fd64.sfs, on HDD ...

unsquashfs fd64.sfs # that creates squashfs-root extracted copy
unsquashfs -f -d squashfs multi...sfs # in their date of creation order
mv fd64.sfs fd64.sfs.old
mksquashfs squashfs-root fd64.sfs # I like to add -comp lz4 -Xhc to that
rm -rf squashfs-root
rm multi*.sfs # multi...sfs files are no longer required

There is a multi...base.sfs involved, i.e. two sfs are created after the very first save.

It's a great (my preferred) way to run Fatdog IMO. If you store user based changes/docs outside (HDD) of the Fatdog system then once the system is setup as you like you can just boot, use, shutdown without saving so that you boot the exact same system every time. But where updating that system is relatively easy, boot freshly, apply changes, click the SAVE icon ... done.