How is this avoided with interpreter threads? They can, after all, share data... I reckon that since it's a special case it might be handled specially, whilst other data is not?

Furthermore, today starting a thread is an enourmous performance penalty, because all non shared data is copied. Unlike forking, where we have copy-on-write (for the curious- it's very efficient, because the kernel simply marks all memory pages as readonly, causing write operations to raise an exception from the MMU, to which the kernel responds to making a new copy of the page which the writing process can work on), there is no optimisation of the process. The main advantage I'm looking for in threads is to gain performance due to concurrency on SMP platforms, for small tasks. Starting a thread needs to be cheap for this to be effective. I think a tradeoff of some continuous speed penalty for an efficient startup time, should at least be a choice.

I'll go looking for some reading material, but I'm sick and too tired to concentrate for any reasonable length of time, so I doubt I can introduce any worthwhile discussion to this thread.

-nuffin
zz zZ Z Z #!perl

In reply to Re^2: TIMTOWTDI vs. ithreads by nothingmuch
in thread TIMTOWTDI vs. ithreads by nothingmuch

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