How to find what is using Chip RAM?

Question

My AmigaOS should have more Chip RAM available to use than it reports (only 800 kB). Is there a way to find what is sitting in Chip RAM and how to move it to Fast RAM instead?

Answer 1

Well written programs aren't going to use chip memory instead of other (fast) memory.

I know about CD32 games that allocate a big block of chipmem so they can stuff all audio/copper data and other data in one single hunk but workbench programs don't do that, so I'd drop the "move chip ram to fast ram" idea completely.

However, it's possible to prevent too much chipmem to be allocated in the first place

• Floppy drives and peripherals that have DMA access in general use chip memory. If you have more than 1 floppy drive connected, disconnect them.
• Bitplanes are costly: reduce the number of colors of your workbench
• Analyse your startup sequence for "exotic" programs that could be badly written and allocate chipmem where fastmem would be okay, and disable them if not needed. See what happens.

Or: boot with a minimal/conditional startup (for instance detect a mouse button pressed and proceed to a minimal startup sequence if you can't/don't want to use "boot without startup"). Then you can use a few hacks to save a few kilobytes, like "add21k", "add36k" commands. The add21k command frees workbench bitplanes. it's a hack, though

However, I suspect that you need a lot of chipmem to run games that require a lot of chipmem, so there's a killer way to "move chipmem to fastmem": it's whdload (JST, which I have written, is an alternative for kickstart 1.3).

whdload can boot a game that requires a lot of chipmem on a system that uses already too much chipmem to boot that game. It does that by killing the system (but saving its memory in fastmem), running the game with full chipmem available (1MB in your case) and restores the system memory on exit.

Of course the particular game & version needs to be supported by a whdload "slave". But there's a lot of them already done. Besides, whdload is able to install a virtual system (kickstart 1.3 and 3.1) so games using the operating system, and which required booting without startup sequence to maximize chipmem can run from workbench. You just need a good amount of fast memory to run them (4MB is good, 8MB is optimal for most games).