Both P and E cores are run at different frequencies according to the load on M1 chips. This explores how macOS manages their frequencies and why.
performance
How the E and P cores in an M1 Max chip cope with the heavy system workload after login, but still give the user the scope to run apps immediately.
File data stored towards the periphery of the disk is read and written nearly twice as fast as that near the centre. How to take advantage of this.
How to work out how many threads and which cores are needed to achieve a compression rate up to 1.7 GB/s, and how to estimate power and energy.
What’s our purpose? What factors confound the results of tests, and how to eliminate them? Which tests? What should we believe, and where do we go from here?
There’s evidence to suggest that original M1 Macs write more slowly to external SSDs in some configurations. Does this extend to later models with M1 Pro or Max chips?
Using CPU % or Energy values in Activity Monitor appears to show that running code on E cores is less efficient than on P cores. Don’t believe a word of it.
If apps control the Quality of Service, which sets how macOS allocates them to different processor cores in an M1 chip, how can we have any control?
Before deciding on internal and external storage, you need to be realistic about the performance it will achieve. Here are the numbers – and a couple of things we tend to forget about.
Select a test, time it, and compare the result with those from other systems. Choose whether to use a synthetic or application benchmark, and don’t forget your confirmation bias.
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