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Re:A Fast, Growable Array with Stable Pointers in C by loeg on Wednesday August 06, 2025 @07:52PM (#44819209)
amd64 has had 48-bit addressing / 4-level paging from the beginning.
Re:A Fast, Growable Array with Stable Pointers in C by hinkley on Thursday August 07, 2025 @07:21PM (#44831612)
I must be thinking of intel’s failed 64 bit attempts prior to amd64 winning.
Re:A Fast, Growable Array with Stable Pointers in C by wittystick on Friday August 08, 2025 @08:37PM (#44843088)
Physical addresses may be limited to 40 bits, but 48-bit virtual addresses have been the norm since 4-level paging.
Re:A Fast, Growable Array with Stable Pointers in C by bonzini on Wednesday August 13, 2025 @07:09PM (#44894963)
You're probably thinking of PAE (36 bit physical address space on 32 bit virtual address space). But Intel for quite some time had a 36 bit physical address space limit on 64-bit consumer processors, even if the virtual address space was 48 bits. I think it only changed 5 years ago or less.