in reply to Threading vs perl

However, does perl really need threads?
Yes.

Would you use them if they were available in stable form?
Certainly.

Is current implementation solid enough?
No. Well OK just maybe, but as I understand it spawning a new thread means copying all memory structures (kinda like a fork), which means growth in memory use. (Even with copy on write, because you have to spend a page to toggle a bit) The advice I've read is to spawn all your threads at startup time when the memory footprint is low, and that gives me an icky feeling about the whole thing. I hope Perl6 will include Java-like threads (only good).

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Re^2: Threading vs perl
by BrowserUk (Patriarch) on Jun 22, 2005 at 17:15 UTC
    The advice I've read is to spawn all your threads at startup time when the memory footprint is low ...

    You can also spawn a thread factory early in your program before you load any modules. You can then load (require) the modules needed by your main thread, and when you need to spawn a thread, have the thread factory do it for you.

    Each new thread created by the thread factory will be a duplicate of the first thread created with it's low(ish) memory footprint, rather than a duplicate of the main thread as would be the case if your spawned it from there.

    With this technique, you can more cheaply create new threads, that only load what they individually need, as you need them rather than having to start them all at the beginning.

    It is a shame the lengths you have to go to defeat the rediculous default behaviour :(

    I hope Perl6 will include Java-like threads.

    I hope that Perl6 will have both User threads (Java-like) and Kernel threads (Perl5-like iThreads--'cept without the enforced duplication).

    Spawning an iThread should just start the function I pass it in a new interpreter running in a new system thread, and leave me to decide what to load there.

    The User thread scheduler would be loaded as a module into one or more Ithreads and be scheduled cooperatively.


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Re^2: Threading vs perl
by jfroebe (Parson) on Jun 22, 2005 at 16:15 UTC

    I wholeheartedly agree with you.

    Although, the previous replies seemed to galvanize around the whole windows vs unix/linux debate with varying degrees knowledge.

    Jason L. Froebe

    Team Sybase member

    No one has seen what you have seen, and until that happens, we're all going to think that you're nuts. - Jack O'Neil, Stargate SG-1