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A comment on 64-bit ARM chips in iPhone 5S serve up taste of Intel-free future for Apple. Parent comment

Re:64-bit ARM chips in iPhone 5S serve up taste of Intel-fre... by vardump on Wednesday September 11, 2013 @05:51PM (#6370369)
64-bits has little to do with amount of addressable memory. In fact, 32-bit and 64-bit processors can address just as much. For example, 32-bit ARMv7 Cortex A15 can address up to 1TB of memory.

The only difference is amount of physical RAM you can map at once. Only virtual address space is limited in 32-bit processors. But even then, you can change the virtual-to-physical mappings at runtime. It's only inconvenient.

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Re:64-bit ARM chips in iPhone 5S serve up taste of Intel-fre... by mikeash on Wednesday September 11, 2013 @07:06PM (#6370776)
In theory true, but in a practical sense, roughly no real-world programs are going to use more RAM than they can actually address with a raw pointer, which means that roughly no real-world programs are going to take advantage of more than 4GB of RAM on a 32-bit CPU.
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