3 ms·

I’m not sure where you’ve gotten this information but I would recommend you do some more research. There is a lot of great info about operating systems - speci

I’m not sure where you’ve gotten this information but I would recommend you do some more research. There is a lot of great info about operating systems - specifically ring0 vs ring1 for the context switch overhead. Meanwhile, only Python and Ruby had GILs. Async/await became popular through JavaScript and C#. Now very popular in Rust as well. None of these runtimes have a GIL. Async/await or Fibers (C++, Go, Java 21) are entirely about context switching overhead.

vitus 3y ago
> Async/await became popular through JavaScript and C#. Now very popular in Rust as well. None of these runtimes have a GIL. To be fair, while typical JS implementations do not have a GIL, it's usually unnecessary due to the runtime being single-threaded. In case anyone else is curious when the above languages grew this feature: (F# piloted this in the 1.x days, back in 2009 or earlier.) It seems like C# developed this feature first in 5.0 in 2012, followed by JS (Dec 2016 in Chrome, widely supported across other major browsers within a few months). Python 3.7 came out in 2018, Ruby 3.0 came out in 2020. Async/await landed in C++20 via coroutines, and Java 21 landed last month. Rust grew this feature in 2018, which landed in the stable channel in 1.39 (Nov 2019). Golang has had goroutines / channels since day 1.
- dragonwriter 3y ago
  > To be fair, while typical JS implementations do not have a GIL, it's usually unnecessary due to the runtime being single-threaded. Yeah, "we avoid a GIL because we don't offer threads at all" is, like pre-1.9 Ruby's, "we don't have a GIL because are threads are 1:N green threads" both technically "no GIL" but also worse for thread-based parallelism, then "we have native threads, but there is a GIL, which native code can release". > Ruby 3.0 came out in 2020. Ruby 3.0 doesn't have async/await, though. There's a third-party colorless Async gem, and built in constructs (that require a scheduler implementation) for lower-friction asynchronous programming (async as an approach has been popular for Ruby for quite a while), but not with async/await syntax in either case.
  - vitus 3y ago
    > Ruby 3.0 doesn't have async/await, though. There's a third-party colorless Async gem, and built in constructs (that require a scheduler implementation) for lower-friction asynchronous programming (async as an approach has been popular for Ruby for quite a while), but not with async/await syntax in either case. (I haven't written anything in Ruby in roughly a decade, so I'm happy to defer to anyone who's actually followed the language the whole time) That's fair. I had skimmed and found some reference to the async gem relying on Fiber::SchedulerInterface which was introduced in 3.0, although it apparently existed back in 2017. There's similarly the async-await gem by the same org (also first released in 2017), which at least partially supports that syntax. But in either case, it's not a native language feature.
otabdeveloper4 3y ago
You should take your own advice, because have no clue what a context switch even is. P.S. C++ async is entirely about running on embedded hardware, not about "overhead". P.P.S. All garbage-collected languages have a GIL of some sort. This is the real reason GC languages aren't used in systems programming, not GC pauses.

vitus 3y ago

> Async/await became popular through JavaScript and C#. Now very popular in Rust as well. None of these runtimes have a GIL. To be fair, while typical JS implementations do not have a GIL, it's usually unnecessary due to the runtime being single-threaded. In case anyone else is curious when the above languages grew this feature: (F# piloted this in the 1.x days, back in 2009 or earlier.) It seems like C# developed this feature first in 5.0 in 2012, followed by JS (Dec 2016 in Chrome, widely supported across other major browsers within a few months). Python 3.7 came out in 2018, Ruby 3.0 came out in 2020. Async/await landed in C++20 via coroutines, and Java 21 landed last month. Rust grew this feature in 2018, which landed in the stable channel in 1.39 (Nov 2019). Golang has had goroutines / channels since day 1.

dragonwriter 3y ago
> To be fair, while typical JS implementations do not have a GIL, it's usually unnecessary due to the runtime being single-threaded. Yeah, "we avoid a GIL because we don't offer threads at all" is, like pre-1.9 Ruby's, "we don't have a GIL because are threads are 1:N green threads" both technically "no GIL" but also worse for thread-based parallelism, then "we have native threads, but there is a GIL, which native code can release". > Ruby 3.0 came out in 2020. Ruby 3.0 doesn't have async/await, though. There's a third-party colorless Async gem, and built in constructs (that require a scheduler implementation) for lower-friction asynchronous programming (async as an approach has been popular for Ruby for quite a while), but not with async/await syntax in either case.
- vitus 3y ago
  > Ruby 3.0 doesn't have async/await, though. There's a third-party colorless Async gem, and built in constructs (that require a scheduler implementation) for lower-friction asynchronous programming (async as an approach has been popular for Ruby for quite a while), but not with async/await syntax in either case. (I haven't written anything in Ruby in roughly a decade, so I'm happy to defer to anyone who's actually followed the language the whole time) That's fair. I had skimmed and found some reference to the async gem relying on Fiber::SchedulerInterface which was introduced in 3.0, although it apparently existed back in 2017. There's similarly the async-await gem by the same org (also first released in 2017), which at least partially supports that syntax. But in either case, it's not a native language feature.

otabdeveloper4 3y ago

You should take your own advice, because have no clue what a context switch even is. P.S. C++ async is entirely about running on embedded hardware, not about "overhead". P.P.S. All garbage-collected languages have a GIL of some sort. This is the real reason GC languages aren't used in systems programming, not GC pauses.