4 ms·
> Would someone like to explain what is wrong with the idea that people who care about CPU-heavy computation also need to care about the performance of the lang
by epidemian 9y ago
> Would someone like to explain what is wrong with the idea that people who care about CPU-heavy computation also need to care about the performance of the language they are using rather than just downmodding it?
I didn't downvote you, so i'm not sure, but maybe it was because of the condescending tone (assuming what they care about from a simple question and telling them what they should care for instead), aaand not answering their question about parallelism in the first place.
- jerf 9y agoI didn't assume, the question contained "CPU-heavy", and the answer is relevant because it's a common misconception that you can make up for a slow language with parallelization, but you can't. If you've got a CPU-heavy task, you will find in practice that even using a lot of threads you'll be lucky to get even a 3x speedup on clock time, unless your problem is 100% strictly embarrassingly parallel. (I've tried a few times, which is where the 3x comes from. It's all I was able to get and my tasks were very close to embarassingly parallel, but the cruel nature of Amdahl's law is that it takes only very slight non-parallel components to wreck your speed.) It's not a viable solution in practice.
- epidemian 9y agoI see your point now, and i agree. Maybe the original message could've been phrased differently, or maybe it was my fault for misinterpreting it :)