site_archiver@lists.apple.com Delivered-To: darwin-kernel@lists.apple.com On Mar 5, 2006, at 11:21 AM, Tony Scaminaci wrote: Not for a user-space application. How do you determine the amount of "free physical RAM"? You don't. You're mistaken. = Mike _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-kernel mailing list (Darwin-kernel@lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-kernel/site_archiver%40lists.a... Is there a system command or kernel call that returns the physical address corresponding to the logical address allocated by malloc? In my code, I first do a malloc for all of the free physical ram followed by mlock. mlock will not necessarily allow you to wire all available memory into your application, since the system requires a certain amount of free memory in order to operate. Because I'm only allocating from the free physical ram pool, all allocated memory resides in ram (which it must for a memory test application). This assumes a very naive model for your RAM test application, and one that cannot be supported by a modern operating system while running. However, the start address returned by malloc is a local address which I can't figure out how to map to the physical DIMM. If I run two instances of the program at the same time and allocate half the free ram to each instance, both instances have the same local start address. How does one figure out the physical address corresponding to these local addresses returned by malloc? Also, I'm under the impression that the memory manager doesn't run in single-user mode. Does that mean that these local addresses are really physical addresses in single-user mode? This email sent to site_archiver@lists.apple.com