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digitalmars.D - Re: The future of concurrent programming

Heh; it's not too bad once you get used to it. The most important thing to keep
in mind is taht all the concurrent programming features people hate (locks,
etc.) are usually unnecessary and possibly even bad for performance. I read
somewhere that something like 60% of locks (in Java, specifically, but this
probably applies to most imperative languages), are actually bad for
performance, since it takes longer to acquire all those locks than to allocate
immutable objects and use AtomicReferences, etc (memory's cheaper than
processing power these days). Of course, that's not possible in all cases, but
when it is it's a great boon.

Even if you can't just pass stuff around/use immutables for something, needing
to use more than a few locks/muticies generally indicative of tight coupling
between modules.

Often, the fewer locks/muticies you use, the better your performance and peace
of mind. I haven't tried any multi-threaded coding in D, but with a whole set
of atomic variables and transaction support in Tango, it should end up being
pretty painless.

Daniel Keep Wrote:

 freeagle wrote:
 Why do people think there is a need for another language/paradigm to
 solve concurrent problem? OSes deal with parallelism for decades,
 without special purpose languages. Just plain C, C++. Just check Task
 manager in windows and you'll notice there's about 100+ threads running.
 If microsoft can manage it with current languages, why we cant?

We can; it's just hard as hell and thoroughly unenjoyable. Like I said before: I can and have written multithreaded code, but it's so utterly painful that I avoid it wherever possible. It's like trying to wash a car with a toothbrush and one of those giant novelty foam hands. Yeah, you could do it, but wouldn't it be really nice if someone would go and invent the sponge and wash-cloth? -- Daniel -- int getRandomNumber() { return 4; // chosen by fair dice roll. // guaranteed to be random. } http://xkcd.com/ v2sw5+8Yhw5ln4+5pr6OFPma8u6+7Lw4Tm6+7l6+7D i28a2Xs3MSr2e4/6+7t4TNSMb6HTOp5en5g6RAHCP http://hackerkey.com/

May 29 2007