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by laumars 1728 days ago
This is where profiling helps more. Find the weak parts of the code, try to optimise those. If the language proves to be a barrier then you have a justification for a rewrite.

All too often people don’t understand how to performance tune software properly and instead blame other things first (eg garbage collection)
1 comments
bluGill 1728 days ago
Most slow languages make escape to C easy for cases where the language is the issue. Most fast languages make writing a C APIed interface easy, so if the language is your issue just rewrite the parts where that is the problem.

Of course eventually you get to the point where enough of the code is in a fast language that writing everything in the fast language to avoid the pain of language interfaces is worth it.

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laumars 1728 days ago
And there’s time when even C isn’t sufficient and a developer needs to resort to inlined assembly. But most of the time the starting language (whatever that might be) is good enough. Even here, the issue wasn’t the language, it was the implementation. And even where the problem is the language, there will always be hot paths that need hardware performant code (be that CPU, memory, or sometimes other devices like disk IO) and there will be other parts in most programs that need to be optimised for developer performance.

Not everyone is writing sqlite or kernel development level software. Most software projects are a trade off of time vs purity.

That all said, backend web development is probably the edge case here. But even there, that’s only true if you’re trying to serve several thousand requests a second on a monolithic site in something like CGI/Perl. Then I’d argue there’s not point fixing any hot paths and just rewrite the entire thing. But even then, there’s still no need to jump straight to C, skipping Go, Java, C#, and countless others.

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pjmlp 1728 days ago
Except when the program is actually written in C, then better hold the Algorithms and Data Structures book and dust it off, or Intel/AMD/ARM/... manuals.
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bluGill 1728 days ago
Algorithms and data structures come BEFORE dropping to c.

These days it is rare that you can beat your compiler with hand machine code, and even if you can it isn't worth it because the difference is typically small and only applies to one specific machine.

Of course once in C you can often think about memory locality and other cache factors that higher languages hide from you.

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pjmlp 1728 days ago
Many applications still start in C, there is no dropping into C.
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