At some point, is this really python?

Posted Jul 26, 2025 17:51 UTC (Sat) by marcH (subscriber, #57642)
In reply to: At some point, is this really python? by pizza
Parent article: Deep immutability for Python

> I'm sorry, but if the hardware is not doing more than one thing at once, your software is not actually doing anything in "parallel". (It could be "concurrent" however..)

OK, so now you're making this interesting distinction. But earlier you wrote:

> > > Parallel programming is a lot easier when when your hardware only executes one thread a time (?!?)

... which makes no sense when making the "concurrent vs actually parallel" distinction. So, before replying earlier I auto-corrected this to:

> > > CONCURRENT programming is a lot easier when...

... which 1. makes some sense. 2. is the more common topic.

And then we talked across each other.

"Concurrent is hard" is a topic more common than "parallel is hard" because correctness comes first. Crashing really fast is not useful.

I mean these are considered not easy no matter how many cores you have:

https://docs.kernel.org/locking/
https://docs.kernel.org/RCU/
https://docs.kernel.org/core-api/wrappers/memory-barriers...

If the hardware executes only one thread at a time, then it's only going to hide some bugs. But hiding bugs does not make concurrent programming easier, the code must be structured the same.