Benefits of being unified
But Apple isn’t integrating memory into its systems-on-a-chip out of spite. It’s doing it because it’s an approach that can lead to some dramatic speed benefits.
The M1 processor’s memory is a single pool that’s accessible by any portion of the processor. If the system needs more memory for graphics, it can allocate that. If it needs more memory for the Neural Engine, likewise. Even better, because all the aspects of the processor can access all of the system memory, there’s no performance hit when the graphics cores need to access something that was previously being accessed by a processor core. On other systems, the data has to be copied from one portion of memory to anotherβbut on the M1, it’s just instantly accessible.
Apple Unified memory architecture
Apple
These new Macs are, in their way, kind of alien. The tradition in personal computers was that everything was modular, an outgrowth of the early PC era. Even though the Mac never participated in the build-a-PC ethos, the parts Apple used to assemble Macs came from that industry. Compare that with the smartphone, where Apple has continued to integrate more portions of the system into its single processor package in order to increase efficiency. These new Macs are far more like smartphones than like traditional PCs.
