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0 pointsdevxpy7y ago0 comments

> deal with serialization and communication

I thought a lot about this problem, for over 2 years, and came up with zproc

Basically,

> It lets you do message passing parallelism without the effort of tedious wiring.

You'll be doing message passing without ever dealing with sockets!

Also, Shared memory parallelism is hard to get right irregardless of which language you use. I would recommend strongly against it, unless you're writing some really really really niche thing where message passing is a bottleneck (it isn't most of the time)

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armitron7y ago

The mantra that shared memory parallelism is hard to get right to the point where such platitudes as "unless you're writing some really really really niche thing" are uttered is entirely erroneous I find, through my own experience.

There are idiot-proof thread-safe datastructures and producer/consumer APIs that map extremely well to most problems that come up in practice in the domain, that one should confidently use. Refusing to do shared memory parallelism because of the _abstract potential for havoc_ rather than any practical justifications based on the problem-at-hand is throwing out the baby with the bathwater and is not the mark of competent engineering.

devxpyOP7y ago

This talk (hopefully) conveys my point across

https://www.youtube.com/watch?v=9zinZmE3Ogk

devxpyOP7y ago

You must be some sort of programming GOD, I guess.

The problem is that its _hard_ to get right.

For example - It's not trivial to use locks when you're working at an abstraction level higher than operating systems. Most people don't even realise there is a race in their application, because locks are inherently non-enforcing. Code written in locks is also really hard to read and reason by.

Message passing just makes it a little more trivial to avoid the pitfalls associated with parallel programming.

I also found that it lets you avoid busy waiting in certain places, which is always a performance advantage :)

Can you shed some light on those "idiot-proof thread-safe datastructures"?

twblalock7y ago

I do concurrency in Java all the time with CompletableFuture and threadsafe data structures provided by various libraries, e.g. the Guava caches, and I rarely need to use locks or semaphores. It's a good set of abstractions that make concurrency pretty close to idiot-proof.

Futures in particular make it easy to write concurrent code close to the way you would write single-threaded code, because all of the threading is handled behind the scenes.

TickleSteve7y ago

busy-waiting is a valid technique for some use-cases (and gives better performance in those situations) than other techniques.

Please research your topic.

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TickleSteve7y ago

you claim "To make utterly perfect MT programs (and I mean that literally)".

you've rediscovered message-passing... please take an elementary CS course on parallel systems.

That claim is naive in the extreme.

devxpyOP7y ago

That's not my claim man, its written in the zguide

http://zguide.zeromq.org/page:all#Multithreading-with-ZeroMQ

Maybe I should've just linked it there,sorry!

Okay, I will take that course and get back, thanks for the suggestion.

P.S. You just implied Pieter Hintjens is naive. You have to live with that now :(

TickleSteve7y ago

I think you took that claim out of context:

"By "perfect MT programs", I mean code that's easy to write and understand, that works with the same design approach in any programming language, and on any operating system, and that scales across any number of CPUs with zero wait states and no point of diminishing returns."

That doesn't mean to say its "perfect" or "solves" multithreading, just that its easy to write and understand and portable across architectures. That says nothing of how optimal it is for concurrency or parallelism ease-of-use wise or performance-wise, just that its 'easy'.

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armitron7y ago

devxpyOP7y ago

This talk (hopefully) conveys my point across

https://www.youtube.com/watch?v=9zinZmE3Ogk

devxpyOP7y ago

You must be some sort of programming GOD, I guess.

The problem is that its _hard_ to get right.

Message passing just makes it a little more trivial to avoid the pitfalls associated with parallel programming.

I also found that it lets you avoid busy waiting in certain places, which is always a performance advantage :)

Can you shed some light on those "idiot-proof thread-safe datastructures"?

twblalock7y ago

Futures in particular make it easy to write concurrent code close to the way you would write single-threaded code, because all of the threading is handled behind the scenes.

TickleSteve7y ago

busy-waiting is a valid technique for some use-cases (and gives better performance in those situations) than other techniques.

Please research your topic.

1 more reply

TickleSteve7y ago

you claim "To make utterly perfect MT programs (and I mean that literally)".

you've rediscovered message-passing... please take an elementary CS course on parallel systems.

That claim is naive in the extreme.

devxpyOP7y ago

That's not my claim man, its written in the zguide

http://zguide.zeromq.org/page:all#Multithreading-with-ZeroMQ

Maybe I should've just linked it there,sorry!

Okay, I will take that course and get back, thanks for the suggestion.

P.S. You just implied Pieter Hintjens is naive. You have to live with that now :(

TickleSteve7y ago

I think you took that claim out of context:

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