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Comment by dlisboa | Hacker News Reader

> Most people, most of the time, doing most web work, are so thoroughly outclassed on speed by their web framework and server that the speed of their choice is irrelevant. Which means they should be selecting based on all the other relevant features.

I disagree with that as the choice of framework doesn't impact just the request/response lifecycle but is crucial to the overall efficiency of the system because they lead the user down a more or less performant path. Frameworks are not just HTTP servers.

Choosing a web framework also marries you to a language, hence the upper ceiling of your application will be tied to how performant that language is. Taking the article's example, as your application grows and more and more code is in the hot path you can very easily get into a space where your requests that took 50ms now take 500ms.

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You can, without loss of generality, simply insert "holding the language constant" if you like into the essay without losing the point I am trying to make, where the question of what language to choose is mostly orthogonal to the point I'm making in that particular essay.

In other contexts I'm a huge proponent of validating that your language is fast enough. There's a constant low-level flow of "we switched from X to Y and got Z% speedup" articles on HN, and while the details of the articles are often quite interesting, with rare exceptions I find that I read them and conclude that it was an error to ever have used X in the first place and the team should have been able to tell immediately that it wasn't going to be a good solution. Exceptions include "we were a startup at the time and experienced rather substantial growth" and the rare cases where technology X is just that much faster for some particular reason... though probably not being a "scripting language" as nowadays I'm not particularly convinced they're all that much faster to develop with past the first week, but something more like "X had a high-level but slow library that did 90% of what we needed but when we really, really needed that last 10% we had no choice but to spend person-years more time getting that last 10% of functionality, so we went with Y anyhow for the speed".

You make an assumption here that the software is also constant or static.

> There's a constant low-level flow of "we switched from X to Y and got Z% speedup" articles on HN, and while the details of the articles are often quite interesting, with rare exceptions I find that I read them and conclude that it was an error to ever have used X in the first place and the team should have been able to tell immediately that it wasn't going to be a good solution.

The language X was probably a good solution at first. Then the company started to increase its product surface or acquired enterprise customers. Now you have new workloads that were not considered and the language is no longer suited for it.

Most likely a decision is made to not introduce a second language to the company just for these new workloads as that complicates the architecture, not to mention hiring and managing, so you stay with language X and try to make do. Now you have language X doing more than it is suited for and response times often increase due to that.

This isn't really a case of startup growing pains, just that software itself cannot know ahead of time every application it'll have. You can choose a "mostly fast for all use cases" language and bet that your applications will fit those general use cases, this means you win small but also lose small.

> The language X was probably a good solution at first.

I would contest even that. Most of the time it's a fight or flight response by the devs, meaning that they just go with whatever they are most comfortable with.

In the previous years I made good money from switching companies away from Python and Rails, to Elixir and Golang. The gains were massive and maintainability also improved a lot.

Of course, this is not advocacy for these technologies in particular. Use the right tool for the job is a popular adage for good reasons. But my point is: people don't use the right tool for the job as often as many believe. Mostly it's gut feelings and familiarity.

And btw I am not trashing on overworked CTOs opting for Python because they never had the time to learn better web tech. I get their pain and sympathise with it a lot. But the failing of most startup CTOs that I observed was that they fell into control mania and micro-management as opposed to learning to delegate and trust. Sadly that too is a function of being busy and overworked so... I don't know. I feel for them but I still want better informed tech decisions being made. At my age and experience I am extremely tired and weary of seeing people make all the same mistakes every time.

Between Python and Elixir or Golang, I’ll stick with Python for an exploratory side project.

It’s just a better fit when you’re not quite sure what you’re building. You just gain more on the 99% of projects that never go anywhere than you lose on the one that you end up trying to turn into a real product. So calling them better web tech assumes a lot about the development process that isn’t guaranteed.

You might be proving my point here because Elixir is amazing for exploration. You literally generate a project and then can immediately fiddle with it to your heart's content in a REPL.

As said though, I don't judge people who go by familiarity. But one should keep an open mind, and learning some of the modern languages (like Elixir) is much less work than many believe.

A better web tech in this case refers to having the potential to scale far above what Python can offer + have a very good developer experience. To me those two are paramount.

You can do a similar Python REPL. So I’m really unsure what you mean here? I mean it’s a little better for displaying data structures but I never really found that particularly useful.

Okay. Not contesting that. Use what you like. My point here was that one does not have to choose between "easy to use and iterate with" and "future-proof". These days you can have both. Elixir, Golang and Rust seem to offer those. Python in my experience only has the former, in terms of performance that inevitably ends up being a bottleneck at one point.

It's also true that many projects will never hit that point. For those Python is just fine. But I prefer to cover my bases in the last years, and have not been disappointed by any of the 3 PLs above.

RE: your edit, Elixir's REPL allows modifying the app in-place but I have not worked with Python in a long time and it might have that as well. Can't remember. Also you can temporarily change an app in production which made fixing certain elusive bugs almost trivial, many times. As much as I love Golang and Rust they got nothing on Elixir's ability to fix your app literally in real time. Then when you are confident in the fix, you make the actual code change, merge it and deploy.

Thanks, I misunderstood your point.

Sure Elixir is fine to work with, the thing is in the back of my mind I’m thinking it’s way more likely to end up embedding Python libraries in Elixir code than the reverse. It’s those little bits of friction that I’m avoiding because the start of a project is play. Soon enough the perfectionist side of me may get involved, until then the goal is to maximize fun so I actually start.

Anyway I get your standpoint and even somewhat agree, it just doesn’t work for me.

My crossover point for where I'd rather be using a static language than a dynamic one for exploration is about a week in the modern era.

In 1999 I'd agree with you completely, but static languages have gotten a lot better.

There are some cases where libraries may entirely dominate such a discussion, e.g., if you know Ruby on Rails and you have a problem right up its alley then that may blow away anything you can get in a static language. But for general tasks I find static languages get an advantage even in prototyping pretty quickly nowadays. What extra you pay generally comes back many times over in the compiler's instant feedback.

And for context, I would have called Python my favorite language from about 2000 to probably 2015 or so. This preference wasn't from lack of familiarity. Heck, I don't even regret it; if I had 2000 to 2015 to do all over again I'm not sure I'd do much differently. Static languages kind of sucked for a good long time.

You can also squeeze performance out of most languages by knowing the bottlenecks and working around them. Even Go you can squeeze performance out of if you really need to and want to.

Go is far from the slowest language even though it has GC.

If we allow for warmup, Java is pretty fast for many workloads.

https://madnight.github.io/benchmarksgame/go.html

Java is very fast. You just have to account for the amount of absolutely terrible written Java code full of 6 levels of inheritance, 6 levels of nested loops and AbstractFactoryFactoryFactoryProviderImpls out there to slow it down. I swear I have seen so much Java code that in the name of "abstraction" and "maintainability" they would take x + y and turn it into 8 classes and method calls.

Yeah, I have been disenfranchised by this style of programming. Its why I prefer languages like Python, when you use objects / classes as needed.

Modern Java, obviously is still objects everywhere, but the deep inheritance is really discouraged. Interfaces with default implementations, records, lambdas. There is just a lot that has moved the culture away from that style of programming, but not all places have moved.

It's a shame that this Java culture left its mark on the Python standard library (notably, in `unittest` and `logging`; the framework for text encodings is also highly boilerplate-y) and a fair bit of the ecosystem (pip has some classes like `class ConfiguredBuildBackendHookCaller(BuildBackendHookCaller)` in its own code, to say nothing of what's vendored) already, though.

Its a shame the over-abstraction culture was so strong that Go did not implement generics until over a decade later because they didn't want all the associated headaches. I know both are somewhat different, but it feels like it all came together as "let's not do that, its a nightmare" essentially.

I think that school of Java is on the way out. Since it's absurdly backward compatible there's a lot of factoryfactory code still lingering, but I don't see it being written a lot.

Though there are a lot of unfortunate "truths" in Java programming that seems to encourage malignant abstraction growth, such as "abstractions are free", and "C2 will optimize that for you". It's technically kinda mostly true, but you write better code if you think polymorphism is terribly slow like the C++ guys tend to do.

Really the fundamental problem is that Java teaches the class as the fundamental unit of abstraction, rather than the function. (It goes so far as to not even have functions that exist independently of a class; even "static" functions must have a class to serve as their namespace.) It is class-oriented programming, not object-oriented programming. When you are really oriented towards objects, naturally you will want functions to be first-class objects. That way you can actually compose them in all the usual ways that objects are composed, instead of being limited to composing them at call time (by sequentially calling them).

When functions are first-class objects, so much of the GoF book just dissipates into the ether. You don't have a "Command pattern", you just have a function that you pass as an argument. You don't have a "Factory pattern", you just have a function that you call to create an instance of some other thing. (And you don't even think about whether your "factory" is "abstract".) And so on and so forth. There is value in naming what you're doing, but that kind of formalism is an architectural smell — a warning that what you're doing could be more obvious, to the point where you don't notice doing it for long enough to think of a name.

Assembly programmers probably think the same thing about C teaching the function as the fundamental unit of abstraction, rather than the basic block.

And Mel thinks the same thing about opcodes.

    Beware. 
    That is not the benchmarks game website.

Here's the current benchmarks game website —

https://benchmarksgame-team.pages.debian.net/benchmarksgame/...

Here are some startup warmup measurements —

https://benchmarksgame-team.pages.debian.net/benchmarksgame/...

I like to characterize it as "the slowest language of the fastest class of languages". In general other compiled languages are faster, though generally we're talking 2 or 3 times at the most (Go doesn't optimize very hard but the language defaulting to unboxed values made up for a substantial proportion of that versus more box-heavy compiled languages), but Go is "generally" faster than nearly all non-compiled languages. "Generally" here means "on general code"; JIT languages can definitely outdo Go on heavily numeric code, even in scripting languages, because JITs are very good at that, but the sort of "general" code that isn't obviously numeric will be faster in Go than any non-compiled language.

This sort of complicated analysis doubles as another example of the difficulty of context-free "fast" and "slow" labels. Is Go "fast"? For a general programming language, yes, though not the fastest. If you reserve "fast" for C/C++/Rust, then no it is not fast. Is it fast compared to Python, though? Yes, it'll knock your socks off if you're a Python programmer even with just a single thread, let alone what you can do if you can get some useful parallel processing going.

> context-free "fast" and "slow" labels

Be specific.

Ask: Faster than what … to do what?

@jerf beat me to it but indeed Golang is one of the very slowest compiled languages out there. I have an okay idea why but I wish someone there made a more serious effort to accelerate it at least by a factor of 2x.

I hate having to mull over the pros and cons of Rust for the 89th time when I know that if I make a service in Golang I'll be called in 3 months to optimise it. But multiple times now I have swallowed the higher complexity and initial slow building curve of Rust just so I don't have to go debug the mess that a few juniors left while trying to be clever in a Golang codebase.

My immediate reaction to seeing

> It is completely normal for web requests to need more than 5 milliseconds to run. If you’re in a still-normal range of needing 50 milliseconds to run, even these very slow frameworks are not going to be your problem.

Is that it apparently does make a huge difference. At least doing CRUD web stuff, my calibration for Scala (so pretty high-level functional code) is to expect under 1 ms of CPU-time per request. The only time I've ever seen something in the 50-100 ms range was when working with Laravel. 5 ms is what I'd expect as the total response time for e.g. a paginated API returning 100+ records with a bunch of optional filters.

Agreed, some languages and frameworks have trouble scaling https://news.ycombinator.com/item?id=45950542

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