| Limit | x86 | x86_64 | ARMv7 | AArch64 |
|---|---|---|---|---|
| System RAM (theoretical) | 32 GBa | 1 TB | 128 GBa | 1 TB |
| System RAM (tested) | 32 GBa | 96 GB | 4 GBa | 8 GB |
| Physical addressing | 36-bit with startup's -x option, 32-bit without | 48-bitb | 40-bit with startup's -x option, 32-bit without | 48-bitb |
| Number of CPUsb | 32 | 32 | 32c | 32c |
| Virtual address spaced | 3.5 GB | 512 GB | 2 GB | 512 GB |
a You need to enable extended addressing by specifying the startup's -x option.
b May be limited further by the hardware.
c Limited to 8 if you're using a version 2 Generic Interrupt Controller (GIC).
d These are the absolute maximum limits for the virtual address space; you can reduce them by setting the RLIMIT_AS resource with setrlimit().