151–160 of 189 posts
Is there any real world application that currently cannot exist without this feature? It seems like a solution looking for a problem.
I can see needing the ability for parallel JS for highly-parallel compute-heavy applications but those already seem serviced by SharedArrayBuffer.
So... why?
I'm late to the party but please for anyone reading this, look into the actor model. Shared mutable state quickly becomes unmaintainanble. It used to be slow to do shared immutable state but that's no longer the case. Today there are many better ways to do shared memory with copy-on-write so data is only copied if it's changed. Think back on history - there are only a handful of computation approaches that have stood…
Of course the language can be made to support it. Given the way Javascript is used, the question is whether supporting it will create a big mess. They have some good ideas. One is that variables can be marked as restricted to one thread. That should be the default. Other languages could benefit from that feature. Python, for example. If you want to get rid of the Global Interpreter Lock, knowing which variables can't…
I share your concerns about the usefulness and implementation of this concurrency strategy. In my opinion, concurrency isn't necessary for JS. If web developers want high-performance, concurrent computing, they should push for adding concurrency to WASM. I doubt concurrency could hurt JS, but I just don't see any reason for it that concurrent WASM doesn't fulfill.
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> Maybe type system help is for people who don’t practice enough. That's like advocating that tests are for people who "can't" write bug free code. Is this the attitude of all JSC developers toward engineering abstractions? I would expect designing a system that JITs third-party code from adversarial parties would lead you to be more cautious about code quality, not less.
Tests are great. No harm in tests. I just don't think that we have sufficient evidence to conclude that using type systems to aid the development of concurrent code actually leads to better concurrent code. Therefore, I err on the side of not using the type system for that purpose so that I can use it for many other things that I think it's really good at. (Just take a look at JSC's source code if you want to see our…
This is like saying we don't have evidence that evolution is real.
Type systems are proof systems. If a type system encodes concurrency safety, and a program is valid under that system, then you can be 100% certain that program doesn't have a race condition bug due to shared state between threads.
If a type system can prove buggy concurrent code is invalid code, then by definition it leads to better valid concurrent code.
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With all due respect, no, it doesn't do fine grained parallelism in the areas I described. Do I think it would be impossible to add parallel styling or layout to WebKit? No. Do I think it would be difficult? Absolutely, primarily because of the difficulty of finding all the concurrency hazards in existing objects and making them thread-safe. It would be easier with a type system that automatically checks for and high…
It would have been a shame if the OSes on which Firefox runs had similarly limited access to shared memory to one particular "safe" style in the spirit of paternalistic caution. Would Rust/Servo have been possible without access to the raw rope?
Your point is that this may enable some currently unimplementable application in JavaScript. The assumption is that Firefox couldn't have existed without a free-for-all shared state thread model, which is very likely false.
I ask you, what applications does free-for-all shared state make possible that SharedArrayBuffer doesn't make possible?
I'm late to the party but please for anyone reading this, look into the actor model. Shared mutable state quickly becomes unmaintainanble. It used to be slow to do shared immutable state but that's no longer the case. Today there are many better ways to do shared memory with copy-on-write so data is only copied if it's changed. Think back on history - there are only a handful of computation approaches that have stood…
Can you go into more detail on which concepts from Pipes in unix, spreadsheets, data management systems like MS Access or FileMaker you're thinking of? My familiarity with the tools is leading to blindness about application...
Earlier quoted context omitted.
> Maybe type system help is for people who don’t practice enough. That's like advocating that tests are for people who "can't" write bug free code. Is this the attitude of all JSC developers toward engineering abstractions? I would expect designing a system that JITs third-party code from adversarial parties would lead you to be more cautious about code quality, not less.
Tests are great. No harm in tests. I just don't think that we have sufficient evidence to conclude that using type systems to aid the development of concurrent code actually leads to better concurrent code. Therefore, I err on the side of not using the type system for that purpose so that I can use it for many other things that I think it's really good at. (Just take a look at JSC's source code if you want to see our…
Btw, in case others are also wondering: JSC is JavaScriptCore.
I'm late to the party but please for anyone reading this, look into the actor model. Shared mutable state quickly becomes unmaintainanble. It used to be slow to do shared immutable state but that's no longer the case. Today there are many better ways to do shared memory with copy-on-write so data is only copied if it's changed. Think back on history - there are only a handful of computation approaches that have stood…
Akka port for javascript
Earlier quoted context omitted.
How? Explain please. https://en.wikipedia.org/wiki/Concurrency_(computer_science) "order-independent components", which makes sense for the Event loop.
I draw the line at whether the interleaving granule is under the programmer’s control or not. For example, I can say that when a task executes on an event loop, no other tasks are executing concurrently to it because the event loop executes tasks sequentially .
Please, no. Shared-by-default heap memory is one of the greatest mistakes ever made in language design. We need a better design justification than it's the easiest thing to implement right now.