What is the difference between different generation processors with the same clock speed when talking about PHP code execution?

Question

I am currently in my final year of a compsci uni course, and am doing a web dev module.

We have to write a PHP script to process a large data file and our score is based on our benchmarked time.

My PC has an i5-4460 @ 3.4GHz. The benchmark PC has an i3-4130 @ 3.4GHz.

Will the code be a similar execution time across both of them? Or will the i3 perform slower.

Just want to get an idea of the time I can expect on the benchmarking system so I can optimise further if needed.

Thanks in advance.

Answer 1

Can you decide which PHP version the benchmark will run on? And is OPcache enabled?

If so target PHP 8.0 and utilize the JIT compiler which runs on x86 CPUs (i.e. Intel/AMD).

Other micro optimisations is using the fully qualified name of the function if you are in a namespace as certain functions are special cased by the VM.

However, your algorithm will always be the bottleneck and if you can improve that you'll get better results than doing tiny language config optimizations.

So benchmark often and try to reduce the big O notation cost. :-)