Will Translated x86 Apps Run Faster than Natively on Some Intel Macs?

[jgorman]

Translating an x86 application using Rosetta 2 to run on Apple Silicon chips will reduce performance. However, as Apple showed at WWDC when demonstrating Maya and Shadow of the Tomb Raider on an A12Z Mac mini developer kit, switching to Apple Silicon may be a net performance increase on some models.

We do not know what kind of performance the first Apple Silicon chips will have, but at the beginning of the PowerPC to Intel transition, the developer kits had Intel chips much slower than the ones in the first Intel macs. Also, Apple wants developers to test their applications to run well even on systems with less performance. So, I anticipate the first retail chips will be faster than the A12Z chip in the developer kit.

Setting aside bugs, if the first retail Apple Silicon chips are as fast as the A12Z, which current Intel models may run native x86 applications slower than the first Apple Silicon models can run them as translated applications?

 

[leman]

For once, the GPU in A12Z is faster than current fastest Intel integrated. If Spec PU benchmarks are any representative, the A12Z should be in the ballpark of the quad core CPUs currently in the lower-end 13” MacBook Pro. I expect the actual Apple Silikon laptops to perform better however. Also, they won’t have to compete against the current Intel lineup, they will have to beat Tiger Lake - decisively - if they are to be a success.

 

[bryce13950]

The answer to this is probably way more complicated than it seems. Some apps probably yes in all cases, and others not so much. A developer may have custom optimizations that they are running that may not translate well through rosetta, but others may actually improve overall execution. Along with that, as apple silicon improves, and Intel Macs stop being released than the answer will likely be yes in all cases. No one will really know until people can start messing around with it.

 

[jgorman]

For once, the GPU in A12Z is faster than current fastest Intel integrated. If Spec PU benchmarks are any representative, the A12Z should be in the ballpark of the quad core CPUs currently in the lower-end 13” MacBook Pro. I expect the actual Apple Silikon laptops to perform better however. Also, they won’t have to compete against the current Intel lineup, they will have to beat Tiger Lake - decisively - if they are to be a success.

That is a good point about the GPU, which would call into question the Intel-based Mac minis now with Intel UHD Graphics 630.

For the laptops, I think the Apple Silicon laptops will outperfrom the lower-end 13" too with less heat and with longer battery life.

 

[jgorman]

The answer to this is probably way more complicated than it seems. Some apps probably yes in all cases, and others not so much. A developer may have custom optimizations that they are running that may not translate well through rosetta, but others may actually improve overall execution. Along with that, as apple silicon improves, and Intel Macs stop being released than the answer will likely be yes in all cases. No one will really know until people can start messing around with it.

You are right. It will depend on the application. One other interesting question is how well a Rosetta 2-translated app can work with hardware that is abstracted. For example, in an x86 video conferencing app, we may get better webcam quality if the app can call the image signal processor in Apple Silicon, like the ones in iPhones.