Computer performance

[Dave2002]

My laptop is getting on for 7 years old. It's a Macbook Pro with an i7 processor. I have older iMacs, which are slow in comparison.

Occasionally I look at the specs of newer moderls.

Tonight I was investigating the performance of some software, which was giving problems on the laptop which has now been updated to Catalina. I tried to replicate the problem on a much older iMac - that dates from 2009. As it happens, the software problem disappeared, but the CPU could not cope with real time operation of the music software I was trying to test. However, it was possible to obtain a good result by not rendering in real time.

After that I wondered if I should at least look at new machines - such as new iMacs. I think the processors have improved, but is it the case that a 2020 machine with an i9 processor will be (say) twice as fast as my laptop, or will it actually be five times as fast, since the newer ones seem to have 6 or 8 cores.

I just don't have a feel for how fast the latest computers actually are. If I bought a new one I'd want it to be faster and more capable than my 2013 laptop.

Also, if i converted my older iMacs to run Linux, would that give a significant speed up for software which ran on Linux and also on MacOS? Many years ago - around 2002 - I noted that some programs running in Linux were effectively two or three times faster than the equivalent programs running in the then MacOS environment. Is that still the case?

[Stunsworth]

I’d wait and see what the ARM Macs offer. Intel machines are probably a dead end at this point in time. I have a couple of 2012 Mac Minis that are showing their age, but I’ll put up with them for 12-18 months to see what gets released.

[Dave2002]

I’d wait and see what the ARM Macs offer. Intel machines are probably a dead end at this point in time. I have a couple of 2012 Mac Minis that are showing their age, but I’ll put up with them for 12-18 months to see what gets released.

I've not kept up with any of this. Is this really due to technology improvements, or is it just about Apple trying to increase its control of the markets? This got me thinking about what I knew about chips - RISC vs CISC, the development of chips like the Transputer, ARM used in the BBC microcomputer, a talk by David Patterson I went to - or maybe he came to us etc. I also wondered if I'd ever done anything with multiprocessing - and then I remembered a very small project run using networked computers, which showed very marginal improvements with a few additional processors - the limitations being due to network overheads. I think that was to check how close we could get to the limits predicted by Amdahl's Laws. Designs using very close coupled processors on chips can do better, but there are still limitations to what can be achieved. I noted the trend during the 1980s-1990s or thereabouts to shift some "difficult" functions into hardware, with the design of special purpose chips for specific hardware functions, but later it seemed that some functions were shifting back to software as the underlying processors gained a very significant increase in speed.

I don't know what compromises are made in modern computers, and how much functionality is pushed into support chips - such as video and audio functionality. A lot of video functionality will be in dedicated graphics processing chips, but i don't know about audio. Does anyone bother about special chips for compressed audio or Midi these days?

I haven't kept up with the "wars" between AMD and Intel either. For a long while it seemed that one company's designs would have a slight advantage for a few years, but then the other would catch up, or have some other merit, such as a cheaper product line etc. I'm guessing that many of the other companies, such as Motorola and Texas instruments are not major players in computer chips - but I could be wrong.

It may be interesting to see Apple move from Intel to its own design of chips - produced by ARM, but will it really make much difference? I don't know.

The world has moved on quite a bit over the last 40 or so years.

[Dave2002]

This article has a view of Apple's move to use ARM chips - https://www.zdnet.com/article/arm-ba...of-windows-pcs

More about business than technology.

[Dave2002]

Here is another article explaining the relationship between Apple and ARM, and the design of chips produced by/for ARM - https://www.zdnet.com/article/introd...w-about-it-now