Get amount of physical memory on the system.
#include <zircon/syscalls.h> uint64_t zx_system_get_physmem(void);
zx_system_get_physmem() returns the total size of physical memory on the machine, in bytes.
TODO(fxbug.dev/32253)
zx_system_get_physmem() returns a number in bytes.
zx_system_get_physmem() cannot fail.
Currently the total size of physical memory cannot change during a run of the system, only at boot time. This might change in the future.
