Found a lot of interesting topics while wading through in my first visit to the site. Thanks to everyone involved. I'll be visiting often, but unfortunately I didn't find an answer to my specific question. I found a topic from 2003 with answers for the Windows counterpart question. The question is...
Does anyone know of a simple utility for the Macintosh that will simulate a decreased RAM environment? (ie. I'm running 256 MB DDR SDRAM on a 10.3.9 Mac OS X box, and I want to simulate a 128 MB environment.) Optionally, is there anything similar to boot.ini in Windows that I can use to modify the RAM usage?
you can always turn off some RAM from the open firmware
'If you need to reduce the installed RAM size (as seen by Mac OS X) for any reason, without actually having to remove a RAM stick (or you want to simulate an arbitrary size that's less than the total installed RAM), you can actually delete the reg entry using the delete-property command, and specify your own reg. Referring to the previous example of the 512 MB PowerBook, the following command essentially disables the second RAM stick (note that this change is not written to NVRAM - it is transient - once you reboot, the other chip will be detected and used as before):
0 > " reg" delete-property ok 0 > 0 encode-int 10000000 encode-int encode+ " reg" property ok '