Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

Questions

patrickcollison.com

Post reply on HN
Print view View original

481–490 of 493 posts

Re: Questions

#481

Post by lisper »

zbentley wrote: post #478
lisper wrote: post #476

Earlier quoted context omitted.

> That is correct. What does that have to do with C? Thread-unsafe code exists in all languages. Yes, that's true. But thread-unsafe GC does not exist in all languages. When GC is provided natively by the language it can be implemented much more safely and efficiently than if you try to shoehorn it in afterwards. > the successful efforts that have been made to remove the GIL in CPython That's news to me. Reference?

https://youtu.be/P3AyI_u66Bw Or search “gilectomy” on LWN. Or check out stackless etc.; it turns out removing the GIL technically is historically one of the easier parts of removing the GIL entirely. It sounds like your main problem is with python’s GC model. Reference counting doesn’t have to be thread-unsafe, but in scripting/interpreted-ish languages that want their threading story to involve seamless (I.e. no spe…

> a GIL or equivalent is the norm

Exactly. And why do you think that is? And in particular, why do you think it is the norm when it is decidedly NOT the norm for Common Lisp and Scheme? The norm for those languages is completely seamless native threading with no special syntax.

Re: Questions

#482

Post by zbentley »

lisper wrote: post #481
zbentley wrote: post #478

Earlier quoted context omitted.

https://youtu.be/P3AyI_u66Bw Or search “gilectomy” on LWN. Or check out stackless etc.; it turns out removing the GIL technically is historically one of the easier parts of removing the GIL entirely. It sounds like your main problem is with python’s GC model. Reference counting doesn’t have to be thread-unsafe, but in scripting/interpreted-ish languages that want their threading story to involve seamless (I.e. no spe…

> a GIL or equivalent is the norm Exactly. And why do you think that is? And in particular, why do you think it is the norm when it is decidedly NOT the norm for Common Lisp and Scheme? The norm for those languages is completely seamless native threading with no special syntax.

It seems like you're arguing in favor of a different language rather than a different implementation of Python. If you wanted to implement, say, the Python class/'object' type in a thread-safe way that didn't rely on a GIL and still freed memory according to approximately the same GC promises as the Python interpreter, I suspect you'd end up implementing something GIL-like in Scheme or Lisp (though my experience extends only to some Clojure and Racket in school, so I may be unaware of the capabilities of some other dialects).

If you wanted to implement a language that looked a little like Python but had your favored Lisp's GC semantics and data structures, I'm sure you could. But it wouldn't be Python.

That's without getting into the significant speed tradeoffs--you can make these languages fast, and I get the impression that there has been a ton of progress there in the last decade. But when Python was being created, and when it had to deal with the implications of concurrency in its chosen semantics? Not so. As I originally said: was it theoretically possible to build Python or equivalent on top of a non-C platform at the time? Sure. But I doubt that would have saved it from tradeoffs at least as severe as the GIL, and it definitely would not have been the pragmatic choice--"let's build it on $lisp_dialect and then spend time optimizing that dialect's runtime to be fast enough for us to put an interpreted scripting language on top of it" seems an unlikely strategy.

Re: Questions

#483

Post by lisper »

zbentley wrote: post #482
lisper wrote: post #481

Earlier quoted context omitted.

> a GIL or equivalent is the norm Exactly. And why do you think that is? And in particular, why do you think it is the norm when it is decidedly NOT the norm for Common Lisp and Scheme? The norm for those languages is completely seamless native threading with no special syntax.

It seems like you're arguing in favor of a different language rather than a different implementation of Python. If you wanted to implement, say, the Python class/'object' type in a thread-safe way that didn't rely on a GIL and still freed memory according to approximately the same GC promises as the Python interpreter, I suspect you'd end up implementing something GIL-like in Scheme or Lisp (though my experience exte…

> If you wanted to implement, say, the Python class/'object' type in a thread-safe way that didn't rely on a GIL and still freed memory according to approximately the same GC promises as the Python interpreter, I suspect you'd end up implementing something GIL-like in Scheme or Lisp

Nope. CLOS+MOP, which exists natively in nearly all CL implementations, is a superset of Python's object/class functionality.

Re: Questions

#484

Post by cambaceres »

repolfx wrote: post #455
cambaceres wrote: post #356

Earlier quoted context omitted.

One other reason is that taxation of income gets extremly high (60 %) when the salary rises above ~$7000/month. This makes people feel that it is impossible to get rich by working for someone else in Sweden, which in turn pushes productive people into startups.

That could only apply to founders who can sell parts of their company, surely. Employee number 1 would still face the same tax ceiling, and you need employees to build a company. The ratio of founders:employees will still be tiny even in Sweden.

No, since stock are offered to early emplyees, which are taxed way lower.

Re: Questions

#485

Post by stefek99 »

> Why are there so many successful startups in Stockholm?

1) work ethics: https://en.wikipedia.org/wiki/Religion_in_Sweden

2) 33 sunshine hours in December: https://en.wikipedia.org/wiki/Stockholm#Climate

> Why is US GDP growth so weirdly constant?

http://economistsview.typepad.com/economistsview/2011/05/doe...

Holy cow.

Great depression.

Hitler coming to power, WW2... Clearly observable.

Re: Questions

#486

Post by garfieldnate »

ddevault wrote: post #90

>Why do there seem to be more examples of rapidly-completed major projects in the past than the present? I'm no historian so this is probably misguided, but I feel like this is an indicator for a society on the decline. Corruption is increasingly rampant in both the public and private sectors, and money is being siphoned off at every step. If we don't figure out how to fix it, mounting costs and inefficiencies could…

Could you explain more about plan9 and acme and why they are amazing? I've never heard of them.

Re: Questions

#487

Post by Sir_Cmpwn »

garfieldnate wrote: post #486
ddevault wrote: post #90

>Why do there seem to be more examples of rapidly-completed major projects in the past than the present? I'm no historian so this is probably misguided, but I feel like this is an indicator for a society on the decline. Corruption is increasingly rampant in both the public and private sectors, and money is being siphoned off at every step. If we don't figure out how to fix it, mounting costs and inefficiencies could…

Could you explain more about plan9 and acme and why they are amazing? I've never heard of them.

I could go on for hours. Just try it yourself, it's free.

Re: Questions

#488

Post by vackosar »

foepys wrote: post #165
unixhero wrote: post #47

Earlier quoted context omitted.

Good observations! You forgot one major thing. This goes for all of Finland, Sweden, Norway and Denmark. The winter is horribly dark and boring. (Unless you're super rich). Therefore most turn inwards, staying indoors, thinking deeply at problems, spending endless afternoons and nights on things. Be it software development, game development, car tuning, car engine work, engineering, knitting or just reading loads of…

I believe to have read somewhere that this is also the reason why so many Russians (and people born in the USSR) are great mathematicians and chess players. Math and Chess are both indoor activities and also absolutely unpolitical, which is a huge plus in an authoritarian regime.

I read somewhere that it was only way to distinguish themselfs and to travel.

Re: Questions

#489

Post by _ea1k »

sdenton4 wrote: post #283
_ea1k wrote: post #256

Earlier quoted context omitted.

lol, I hear people frame the self driving car discussion that way regularly, but it is just wrong. Noone is going to be making human driven vehicles illegal. They may be more like classic cars than regular vehicles at some point, though.

Nah, you'll just see the insurance cost spike to the point where driving is a weekend activity for rich weirdos. Give it a generation and it will be as strange and morally suspect as smoking.

Smoking is a weird analogy. I'd expect a better one to be something like "give it a generation and it will be as strange and morally suspect as a horse and buggy".

Or alternatively, maybe as strange as a motorcycle or vintage MG.

Re: Questions

#490

Post by _ea1k »

allannienhuis wrote: post #272
_ea1k wrote: post #256

Earlier quoted context omitted.

lol, I hear people frame the self driving car discussion that way regularly, but it is just wrong. Noone is going to be making human driven vehicles illegal. They may be more like classic cars than regular vehicles at some point, though.

I wouldn't be surprised to see an increasing number of (express-type) roads or perhaps dedicated lanes where human drivers were not allowed on though, after self-driving capabilities become the norm. (yes I realise that's an assumption). I think people underestimate the cultural impact that self-driving vehicles will have - imagine a whole generation or two after self-driving vehicles are generally available - how ma…

I think you are absolutely right about some limited circumstances that make them the only legal option. But the analogy that I keep making is to classic cars. A lot of them don't have the safety features that we expect today. It isn't uncommon for their owners to say things like "I'm only safe on roads that existed in 1960". It is obviously an exaggeration, but the point is that even today there are plenty of cars that are legal to operate but probably wouldn't be anyone's preference on a busy 70 MPH interstate.

At some point, human driven cars become novelties, just like that. There is no reason to ban them, but as you suggest, maybe there will be some HOV-like lanes where they don't really have access. Or even some time constraints (not during rush hour on some key roads, not in lower manhattan, etc).

Post reply on HN