May 7 “Let Loose” Event - new iPads

[KingOfPain]

As @Nycturne writes below, especially during the early days of big.Little, not every Android maker got that right and had heterogeneous ISAs on the cores with the efficiency cores missing features causing problems.

I should really read post I reply to more thoroughly, because I definitely missed that part.
At least Apple learnt from the previous mistakes of others. I'm sure they will make plenty of their own mistakes (butterfly keyboards, etc)...

 

[dada_dave]

Inspired by @dada_dave I grabbed a bunch of GB6 entries and did a comparison that tries to take the distribution of results into account. The main issue with regular comparisons is that there is a lot of variance in the GB6 entries, so picking two results at random can go either way. By replicating results from several dozens benchmarks we can see a much clearer picture.

View attachment 29376

Courtesy of @leman's scripts I made a couple of more plots:

This first plot shows gains in iso-clock performance since the M1. Had to move to 5% outliers because the HTML5 outliers were insane, going really far up. I did screw up slightly as to what I meant to compare: the above is the M4 iPad Pro 13 inch vs M1 iPad Pro 11 inch, I had to meant to do 13 inch for both, but I don't think it makes too much difference. And I'm too lazy to fix it.

This shows the loss of iso-clock performance in some subtest for the M2 Max when raising clocks (some models had higher clocks). The amount of clock boost was minimal, the performance retraction relative to clock is even more minimal, and the noise is high, but this is why I contend that sometimes even just keeping up with clocks, especially when clocks are raised by nearly 40% can necessitate architectural improvements and be quite an achievement especially when your performance is already so high. Interestingly I spot checked a few Intel and AMD chips, seeing how different boost clocks change performance per clock and I found that within Zen 4 there was a similar retraction of a few percent but for Intel's Raptor Lake it was nearly perfect scaling with clocks. Note this isn't saying that necessarily Intel has better iso-performance but rather their iso-performance scales almost perfectly over their range of clock speeds while AMD's slightly drops off at the high end. Now this was a spot check of each, so it just not be confused with data, but it is interesting. If accurate it could represent a difference in process (TSMC vs Intel) or more likely a difference in core design whereby Intel desktop chips are designed first and foremost with these high frequencies in mind and while AMD's can reach those high frequencies their optimal point is lower. Dunno.

 

[Cmaier]

I think Apple just followed the approach that ARM had been using with big.LITTLE for years: Design the performance and efficiency cores together with the same ISA.

Intel on the other hand combined Core-i and Atom cores to quickly bring a product to the market, and I guess they are still using Atom for the E cores instead of designing a proper efficiency core that has the same ISA as the performance core.

Their first amd64 product was also a kludge. 32-bit ALUs with microcode to stitch things together. That’s how Intel rolls.

 

[dada_dave]

Courtesy of @leman's scripts I made a couple of more plots:

View attachment 29481
This first plot shows gains in iso-clock performance since the M1. Had to move to 5% outliers because the HTML5 outliers were insane, going really far up. I did screw up slightly as to what I meant to compare: the above is the M4 iPad Pro 13 inch vs M1 iPad Pro 11 inch, I had to meant to do 13 inch for both, but I don't think it makes too much difference. And I'm too lazy to fix it.

View attachment 29480

This shows the loss of iso-clock performance in some subtest for the M2 Max when raising clocks (some models had higher clocks). The amount of clock boost was minimal, the performance retraction relative to clock is even more minimal, and the noise is high, but this is why I contend that sometimes even just keeping up with clocks, especially when clocks are raised by nearly 40% can necessitate architectural improvements and be quite an achievement especially when your performance is already so high. Interestingly I spot checked a few Intel and AMD chips, seeing how different boost clocks change performance per clock and I found that within Zen 4 there was a similar retraction of a few percent but for Intel's Raptor Lake it was nearly perfect scaling with clocks. Note this isn't saying that necessarily Intel has better iso-performance but rather their iso-performance scales almost perfectly over their range of clock speeds while AMD's slightly drops off at the high end. Now this was a spot check of each, so it just not be confused with data, but it is interesting. If accurate it could represent a difference in process (TSMC vs Intel) or more likely a difference in core design whereby Intel desktop chips are designed first and foremost with these high frequencies in mind and while AMD's can reach those high frequencies their optimal point is lower. Dunno.

Here's one I think is neat, just a single data point for each mind you but still!

Basically what this shows is that overall the areas where Zen 4 has caught up with M1 in terms of iso-clock performance are the same areas where Apple has improved the most between M1 and M4. My suspicion is these are the tests most amenable to vector and matrix units, see below:

But by and large the areas where Apple is most ahead are the areas with the least improvement. Now again, no error bars, no violins here, but I still think that is extremely interesting. It is also striking how similar the Zen 3 to Zen 4 improvements were to M1 to M4. Of course Zen 3 to Zen was over a shorter period of time, it would be more apt to compare to Zen 5 when it comes out later this year - depending on what chip generation Apple is on by then as well!