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Hello,

I've been staring at the Memory Monitor in Instruments and I am scratching my had. Why is it displaying virtual memory? iPhone OS has no virtual memory. What does it mean?

My concern is that I am getting memory warnings for my iPad app but the apps real memory never exceeds 70MB and the virtual memory never exceeds 180MB?

Could someone please enlighten me?

Cheers,
Doug

A: 

(Virtual memory does not (just) mean using the hard disk as memory, but a technique that transforms addresses used in application to a real physical memory location.)

From New Feature in iPhone OS 3.1 with Snow Leopard: VM Tracker:

The VM Tracker instrument is designed to report on a target process' virtual memory space, showing all of the regions mapped into the address space along with information and statistics relevant to the mapping type. For example, a region that is a memory-mapped file via an mmap call will show as a "mapped file" region and display the path for the file it references. Instruments shows size statistics for each region as well: virtual, resident, and dirty.

KennyTM