Intro

I just bought a shiny new MacBook Pro M1. And had to send it back.

But why?

Well. I am using Macs for the last 18 years. And I also participated in the transition from PowerPCs to Intels. I am primarly a Java dev. Back then it was working for me. The Intels were just so much faster than the PowerPCs (which were really slow).

Now? There's not yet a dedicated Java SDK available (ok - azure got a working one, but there is no official one from openjdk for instance).

So Rosetta provides an emulation to run any x86 app on the arm platform.

The good news: Rosetta's emulation is working nicely. All sorts of brew installed applications work. Java works. Maven works. Netbeans works. All good.

The bad news: When developing software I had the feeling that the M1 Mac is a lot slower than my 3 year old Macbook Pro i7.

Feeling? Well... let's run some tests and check the numbers.

Performance test

Specs for the tests

AdoptOpenJdk 11.0.9.1 (x86)
Maven 3.6.3
MacBook Pro i7 2018 2.7 GHz 16GB versus Macbook Pro 2020 M1 16GB.
Compilation of Ninja - an open source Java framework (https://www.ninjaframework.org/)

Compiling ninja-core (a smaller part of the ninja framework)

2020 MacBook Pro M1: building ninja-core mvn clean verify 31 seconds
2018 MacBook Pro i7: building ninja-core mvn clean verify 13 seconds

Ouch. i7 is 2.3x faster than the (Rosetta) M1.

Compiling ninja (the whole framework)

2020 MacBook Pro M1: building ninja-core mvn clean verify 188 seconds
2018 MacBook Pro i7: building ninja-core mvn clean verify 115 seconds

Ouch. i7 is 1.6x faster than the (Rosetta) M1.

Notes:

This is of course a bit unfair for the M1 Mac because it has to run everything in emulation. But this is the whole point of this article
These are not super-scientific numbers, but I ran the compliations multiple times and the numbers were roughly the same.

I would have expected the new Mac to be as fast in emulation as the 3 year old i7. But that is not the case. It is a lot slower. Thus my current Java workflows are massively impacted by the slow emulation of the x86 Java editions.

Conclusion

What does this mean?

Not much. I am sure the performance will increase substantially once the apps (and especially the java apps) are running natively on the M1 Macs. And of course this is not really a fair comparison. Running something in emulation will be slower.

But for me this is too slow. So I personally cannot use the M1 for productive work. Sad.