And therein lies the problem with node. Its great for rapid prototyping, but things fall apart pretty quickly with CPU laden tasks. That and the whole single threaded thing with node (technically JS) can be a wrecking ball when one task takes too long.
Done properly this also leads to a low memory process that will grab data from an incoming socket stream, transform it, then push that data back out through an outgoing socket stream, only ever keeping a few MB of the stream in working memory at a time. Slap a cluster of these streaming processes together running on a single box to utilize all CPU cores and you can easily push many Mbps of IO through your server quickly and efficiently.
Additionally even if you do have a heavy blocking system IO operation that you can't break up very well you can increase `UV_THREADPOOL_SIZE` when needed to reduce the impact of the blocking.
It really depends on what your most important metric is. If the most important metric is speed then having more control over context switching is often better.
What I'm trying to say is: use the right tool for the job. If your code is CPU intensive either don't use Node or use it exclusively for the IO-bound tasks and spawn jobs (or use a message queue, or whatever) for your CPU-bound needs.
> ... things fall apart ... a wrecking ball...
This one is FUD.
I doubt there are many left on HN or anywhere else that hasn't heard this argument, and a similar proportion who don't know the solution (which is that you use clustering or worker processes for tasks the block the process more than your use case can absorb).
> Its great for rapid prototyping...
This one is true, it is great for rapid prototyping, but the implied point that it's not good for production apps is demonstrably false (as proven by the number of serious and respected companies happily using it in production).
There's an argument to be made about node.js being a form of technical debt, and that's a reasonable point, but it also needs to be made in the context of the huge value of that technical debt.
Update: I actually think Node.js is a contributor of technical debt but that it's worth the cost for the use cases I usually deal with (see point 7 on my post: https://medium.com/@richmarr/technical-debt-and-why-most-peo...)
As Dave pointed out in the blog, we’ve definitely run into our fair share of challenges with the inherent limits of node.js. But on the whole, we’ve found it to strike a good balance between speed of development and performance. In addition to some of the techniques talked about in the post, we’ve also dropped down to C++ add-ons where we have really critical performance sections, and we do coarse-grained load balancing between multiple node processes to distribute computation on multiple cores.
We also have a good bit of shared code between the browser and server (including the Juttle language compiler and runtime) that has been hugely beneficial for us.
YMMV of course.