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> I thought one of the key selling points with Node was an fully async standard library, enabling better scaling in process. We still have an event loop that i

> I thought one of the key selling points with Node was an fully async standard library, enabling better scaling in process. We still have an event loop that is trivially blocked by very simple programmer errors, destroying the whole advantage that you describe here. The fact that Node ships a fully asynchronous standard library doesn't in any way fix the fact that Node is a runtime for a language that itself is a mistake.

nicoburns 7y ago
> We still have an event loop that is trivially blocked by very simple programmer errors, destroying the whole advantage that you describe here. So they fixed the issue that some requests blocked... by making all requests blocking.
- phoe-krk 7y ago
  This is the worst kind of software engineering. There is a massive deadlocking design mistake in the centre of the language - literally a huge red button with DO NOT PRESS printed on it. Thousands of programmers pass it by every single day, or hour, or minute, and the creators of the runtime insist that it is impossible to fix that button whatsoever; instead, all users need to work around it by ensuring that their code in no way presses that red button on purpose or even by accident. These people insist that it is impossible to program normally and in a language that is actually sane and does not advertise obvious and gaping design mistakes as "features of the language". These people advertise the analogue of Python's Global Interpreter Lock as the core foundation of their language. These people advertise Node and the language it implements as practical for implementing multithreaded applications. Posts such as this show what sort of bullshit it is; it is only practical to use Node for parallelism if each single Node instance is only ever run single-threaded. You don't parallelize by running multiple threads, you parallelize by running multiple Node runtimes. This is no longer an act against productivity or usability. This is simply insane and shows one of the most basic things that are wrong about Node's language and approach. It is impossible to write a multithreaded program if your language of choice makes it trivial, and practically unavoidable, to globally lock your whole runtime with every single line of code you write and import as your dependencies.
  - jononor 7y ago
    The blog in question indicates some uncommon and questionable engineering practices with Node.js. There are likely hundreds of success stories for every one like that. The first Node.js service I wrote and maintained, processed thousands of requests in parallel and was successfully in production until the company it was developed for ran out of money.
    - x86_64Ubuntu 7y ago
      But how many of these "questionable" practices get held up as engineering marvels by the creators of the monstrosity? When you look at this blog post, you can see the author really felt a sense of pride in this Frankenstein and wanted to show the whole village.
      - tracker1 7y ago
        I didn't get that impression.. what I got was a few probably common issues that will come up when trying to handle more parallel requests with Node. Note: gRPC doesn't support cluster, so you'd have to manage your own multi-thread (Workers) or multi-process (fork) options.
  - JoeAltmaier 7y ago
    Multithreading is still possible - for clarity of code. Multiple processing threads are running in parallel, but only one at a time. This is a subset of useful applications, but not totally worthless.
    - phoe-krk 7y ago
      Yes, it is possible, and actually works - unless one of your threads blocks the event loop and prevents all others from running. This way it takes a single locking thread to halt the whole system, whereas with standard threads a single stalling thread does not cause all others to starve. This is a risk in Node that multiple other runtimes of other languages do not have.
  - 7y ago
- Vesuvium 7y ago
  It's simple but effective.
duxup 7y ago
>by very simple programmer errors I can't help but also feel that is also an issue and in another given language this issue might not happen ... but they'd hit another. It's so easy to say "don't do X because problem Y won't happen" but hard to predict what happens when you move from (language, platform, or whatever) X to (language, platform, or whatever) Z.... and I suspect people often hit issues and realize that maybe Y wasn't the problem. I see it all the time and I feel like "Wait guies I'm not sure we're fixing the right thing!?!?!" This article raises a lot more questions than answers IMO.
- deleted 7y ago
  [deleted]
deleted 7y ago
[deleted]
davedx 7y ago
> trivially blocked by very simple programmer errors Can you give an example please? I think it's much easier to block a thread with C#'s async programming model than node's...
- dmitriid 7y ago
  Node only has one thread. Everything else follows.
  - coddle-hark 7y ago
    No it doesn’t. We’ve had good models for concurrency in single-threaded systems for a while now.
    - PixyMisa 7y ago
      The model being "don't do that".
    - dmitriid 7y ago
      You say no it doesn't and then speak about concurrency models for single-threaded systems. Choose one :) Node can't not be single-threaded. Because Javascript is. Node.js is single threaded. It has a single event loop in a single thread, and all the "concurrency" is simply queued on that loop. It offloads some tasks to libuv for some system-related tasks but that's it. And the thread pool that libuv creates is very limited. Anything that doesn't end up in libuv (that is, probably vast majority of user code) will only ever run in one thread... because Javascript is single-threaded hence V8 is single-threaded hence Node.js you get the gist. And of course, node.js even has a separate documentation section titled "Don't Block the Event Loop (or the Worker Pool)" [1] because it's trivial to block the event loop. [1] https://nodejs.org/en/docs/guides/dont-block-the-event-loop/ https://nodejs.org/en/docs/guides/dont-block-the-event-loop/
      - willglynn 7y ago
        Not OP, but… concurrency is not the same as parallelism. This is an important hair to split: https://stackoverflow.com/a/24684037/1026671 https://stackoverflow.com/a/24684037/1026671 "Concurrency" doesn't warrant scare quotes even when describing a single threaded program. It's true that Node.js allows one task to block many others, but that's an implementation detail of Node.js, not a guaranteed result which necessarily applies to any program using only one OS thread. Other programs suffer from analogous starvation/deadlock/livelock/priority inversion problems, but those would be implementation details too, not guaranteed results from using multiple OS threads.
earthboundkid 7y ago
Async is just modern cooperative multitasking, and just like the 90s, it's easy to accidentally lock the whole system.
- phoe-krk 7y ago
  We are no longer in the 90s. The code has increased in volume a hundredfold and it comes from literally everywhere. You can no longer trust everything on your machine or your network to be bug-free or otherwise non-hostile. Creating a system in the 21st century that tries to follow ideals from the 90s gives us the kind of idiotism that we can witness here.
  - jerf 7y ago
    I think you may have misinterpreted earthboundkid; the claim isn't that it worked in the 90s, the claim is that it was already broken in the 90s. You are otherwise on the right track, though Node does technically have one advantage, which is that it is a cooperatively-scheduled island in a preemptively-scheluded overall OS. In the 1990s, when the cooperatively-scheduled program was not cooperative, you locked the machine, not the process [1]. There is a reason why Apple went very aggressive with the OSX rewrite; the previous Systems had basically written themselves into a corner where they had to use cooperative multitasking because so much code made use of the implicit promises it provides, yet they could no longer afford to compete with Microsoft if they didn't get off it it, because the complexity just kept going up, up, up and the problem was going to continue getting exponentially worse. For a Node program, you only have to account for the Node program itself, not everything running on the computer. Still, you're in the same exponentially-growing-complexity trap (with a very initially-safe-seeming low exponent, but it still gets you in the end), you just reset yourself back to a point earlier on the curve. [1] There are various details, caveats, interrupts, etc, the picture is more complicated than one sentence can convey, but the principle still held and it was still possible to wedge the machine fairly badly for varying periods of time with simple bad code.
  - winrid 7y ago
    I mean, if you write slow code in a high throughput environment you'll just kill the CPU from context switching between threads instead. It doesn't matter if it's in an event loop or thread per request. Architect things correctly.

nicoburns 7y ago

> We still have an event loop that is trivially blocked by very simple programmer errors, destroying the whole advantage that you describe here. So they fixed the issue that some requests blocked... by making all requests blocking.

phoe-krk 7y ago
This is the worst kind of software engineering. There is a massive deadlocking design mistake in the centre of the language - literally a huge red button with DO NOT PRESS printed on it. Thousands of programmers pass it by every single day, or hour, or minute, and the creators of the runtime insist that it is impossible to fix that button whatsoever; instead, all users need to work around it by ensuring that their code in no way presses that red button on purpose or even by accident. These people insist that it is impossible to program normally and in a language that is actually sane and does not advertise obvious and gaping design mistakes as "features of the language". These people advertise the analogue of Python's Global Interpreter Lock as the core foundation of their language. These people advertise Node and the language it implements as practical for implementing multithreaded applications. Posts such as this show what sort of bullshit it is; it is only practical to use Node for parallelism if each single Node instance is only ever run single-threaded. You don't parallelize by running multiple threads, you parallelize by running multiple Node runtimes. This is no longer an act against productivity or usability. This is simply insane and shows one of the most basic things that are wrong about Node's language and approach. It is impossible to write a multithreaded program if your language of choice makes it trivial, and practically unavoidable, to globally lock your whole runtime with every single line of code you write and import as your dependencies.
- jononor 7y ago
  The blog in question indicates some uncommon and questionable engineering practices with Node.js. There are likely hundreds of success stories for every one like that. The first Node.js service I wrote and maintained, processed thousands of requests in parallel and was successfully in production until the company it was developed for ran out of money.
  - x86_64Ubuntu 7y ago
    But how many of these "questionable" practices get held up as engineering marvels by the creators of the monstrosity? When you look at this blog post, you can see the author really felt a sense of pride in this Frankenstein and wanted to show the whole village.
    - tracker1 7y ago
      I didn't get that impression.. what I got was a few probably common issues that will come up when trying to handle more parallel requests with Node. Note: gRPC doesn't support cluster, so you'd have to manage your own multi-thread (Workers) or multi-process (fork) options.
- JoeAltmaier 7y ago
  Multithreading is still possible - for clarity of code. Multiple processing threads are running in parallel, but only one at a time. This is a subset of useful applications, but not totally worthless.
  - phoe-krk 7y ago
    Yes, it is possible, and actually works - unless one of your threads blocks the event loop and prevents all others from running. This way it takes a single locking thread to halt the whole system, whereas with standard threads a single stalling thread does not cause all others to starve. This is a risk in Node that multiple other runtimes of other languages do not have.
- 7y ago
Vesuvium 7y ago
It's simple but effective.

duxup 7y ago

>by very simple programmer errors I can't help but also feel that is also an issue and in another given language this issue might not happen ... but they'd hit another. It's so easy to say "don't do X because problem Y won't happen" but hard to predict what happens when you move from (language, platform, or whatever) X to (language, platform, or whatever) Z.... and I suspect people often hit issues and realize that maybe Y wasn't the problem. I see it all the time and I feel like "Wait guies I'm not sure we're fixing the right thing!?!?!" This article raises a lot more questions than answers IMO.

deleted 7y ago
[deleted]

deleted 7y ago

[deleted]

davedx 7y ago

> trivially blocked by very simple programmer errors Can you give an example please? I think it's much easier to block a thread with C#'s async programming model than node's...

dmitriid 7y ago
Node only has one thread. Everything else follows.
- coddle-hark 7y ago
  No it doesn’t. We’ve had good models for concurrency in single-threaded systems for a while now.
  - PixyMisa 7y ago
    The model being "don't do that".
  - dmitriid 7y ago
    You say no it doesn't and then speak about concurrency models for single-threaded systems. Choose one :) Node can't not be single-threaded. Because Javascript is. Node.js is single threaded. It has a single event loop in a single thread, and all the "concurrency" is simply queued on that loop. It offloads some tasks to libuv for some system-related tasks but that's it. And the thread pool that libuv creates is very limited. Anything that doesn't end up in libuv (that is, probably vast majority of user code) will only ever run in one thread... because Javascript is single-threaded hence V8 is single-threaded hence Node.js you get the gist. And of course, node.js even has a separate documentation section titled "Don't Block the Event Loop (or the Worker Pool)" [1] because it's trivial to block the event loop. [1] https://nodejs.org/en/docs/guides/dont-block-the-event-loop/ https://nodejs.org/en/docs/guides/dont-block-the-event-loop/
    - willglynn 7y ago
      Not OP, but… concurrency is not the same as parallelism. This is an important hair to split: https://stackoverflow.com/a/24684037/1026671 https://stackoverflow.com/a/24684037/1026671 "Concurrency" doesn't warrant scare quotes even when describing a single threaded program. It's true that Node.js allows one task to block many others, but that's an implementation detail of Node.js, not a guaranteed result which necessarily applies to any program using only one OS thread. Other programs suffer from analogous starvation/deadlock/livelock/priority inversion problems, but those would be implementation details too, not guaranteed results from using multiple OS threads.

earthboundkid 7y ago

Async is just modern cooperative multitasking, and just like the 90s, it's easy to accidentally lock the whole system.

phoe-krk 7y ago
We are no longer in the 90s. The code has increased in volume a hundredfold and it comes from literally everywhere. You can no longer trust everything on your machine or your network to be bug-free or otherwise non-hostile. Creating a system in the 21st century that tries to follow ideals from the 90s gives us the kind of idiotism that we can witness here.
- jerf 7y ago
  I think you may have misinterpreted earthboundkid; the claim isn't that it worked in the 90s, the claim is that it was already broken in the 90s. You are otherwise on the right track, though Node does technically have one advantage, which is that it is a cooperatively-scheduled island in a preemptively-scheluded overall OS. In the 1990s, when the cooperatively-scheduled program was not cooperative, you locked the machine, not the process [1]. There is a reason why Apple went very aggressive with the OSX rewrite; the previous Systems had basically written themselves into a corner where they had to use cooperative multitasking because so much code made use of the implicit promises it provides, yet they could no longer afford to compete with Microsoft if they didn't get off it it, because the complexity just kept going up, up, up and the problem was going to continue getting exponentially worse. For a Node program, you only have to account for the Node program itself, not everything running on the computer. Still, you're in the same exponentially-growing-complexity trap (with a very initially-safe-seeming low exponent, but it still gets you in the end), you just reset yourself back to a point earlier on the curve. [1] There are various details, caveats, interrupts, etc, the picture is more complicated than one sentence can convey, but the principle still held and it was still possible to wedge the machine fairly badly for varying periods of time with simple bad code.
- winrid 7y ago
  I mean, if you write slow code in a high throughput environment you'll just kill the CPU from context switching between threads instead. It doesn't matter if it's in an event loop or thread per request. Architect things correctly.