The performance Difference: Apple’s M1 vs. M2 Processors with Single NAND Chip SSDs

MyWorkDrive was heavily invested in the new ARM based Apple processors during their development, with dev kits and active development of our macOS client in the run up to the M1 launch.

When production units arrived, we eagerly picked up a number of new Macs – M1 Pro for development, Minis for QA and your author picked up a MacBook Air to join in as additional testing. It was important to us to ensure we had a stable, reliable macOS client for early adopters.

The M1 Processor Macs showed to be much faster out-of-the-box than Intel based Macs of similar (and even greater) spec. And the battery life was amazing. Our client worked very well (with some small setup challenges for the file system driver).

When the M2 came out, we looked eagerly to upgrade. Expecting even better battery life and performance increases in the M1 to M2 akin to what we’d see going from Intel to M1.
We were surprised to find the M2 was not much faster, and in some cases actually even slower than the M1 equivalents. Customers noted the same thing. Wondering if we’d changed our software or built something different for the M2 – or what was different. Disk operations like loading directories and file writing are significantly slower on the entry level M2 MacBook Air as compared to an equivalent M1 MacBook.
We hadn’t made any changes, and our dev team didn’t find any reason in the macOS software that would have caused any performance changes. And running macOS Ventura (10.13) on M1 Macs didn’t show the performance issues. At was certainly something in the M2 that was different from the M1, that our software seemed particularly impacted by.

Thanks to community research and articles from The Verge and ArsTechinca (1) (2), we now know that the issue relates to Apple’s choice to use a single NAND chip in the 256gb SSD for the M2 processor machines, instead of two NAND chips which where used in the M1 models.

Disk Speed: A Crucial Aspect of Performance

Disk speed is a critical factor that impacts overall system performance. It determines how quickly data can be read from and written to the storage drive, which affects tasks like booting up the system, launching applications, and handling large files. This is particularly true for MyWorkDrive on macOS using Apple’s File Provider to make remove files available to end users. Files and metadata are retrieved from the MyWorkDrive server and passed through Apple’s file provider to Finder, a process which reads data in via API and writes it to disk.

You’ll have both disk writes (to make the data available) and disk reads (by the user accessing the data), so SSD Performance is critical to smooth operation. The M1 does great. The entry level M2 devices, however, suffer some performance decrement.

Apple’s M1: SSD Performance and Beyond

The M1 processor, combined with its unified memory architecture and high-performance SSDs, led to impressive disk speed gains compared to older Intel-based Macs. This was partly due to the efficient integration of the SSD controller and the increased bandwidth of the M1’s memory subsystem. The result was near-instantaneous app launches, swift data transfers, and reduced wait times.

Apple’s M2: The Single NAND Chip SSD Conundrum

As Apple introduced the M2 processor, it continued to prioritize performance and efficiency. However, in certain lower-range M2 Macs, there’s been a shift in the approach to SSD design. Instead of using a multi-chip SSD configuration, some M2 Macs feature a single NAND chip for their SSDs. This design decision might raise eyebrows, considering the potential impact on disk speed.

The Implications of Single NAND Chip SSDs

Using a single NAND chip for an SSD can have both positive and negative implications for disk speed. On one hand, a single NAND chip can lead to cost savings and potentially improved power efficiency due to reduced complexity. On the other hand, it might result in slower disk speeds compared to multi-chip SSD configurations. This is because multi-chip SSDs can leverage parallelism to achieve higher data transfer rates.

For most users, the M2 Macs are still faster than an equivalent Intel based Mac, and performance is as good or better than Windows laptops, so the M2 is still a solid choice.

However, if you haven’t refreshed 256gb Macs from M1, you might want to stick with M1s.
If you do want to upgrade, you might spend the extra money ($200 as of the writing of this article) to upgrade from the 256gb storage model to the 512gb storage model, for users who have high disk utilization demands – creatives, db users, video editors, etc.