Because, whereas in a compiled langauge each thread consists of little more than a set of cpu registers, a stack and an entry in the system scheduler tables; in Perl, you need those: plus a complete interpreter, plus per-interpreter copies of all non-entrant state.

And as Perl began life as a single-threaded app, its internal state and control structures were never designed from the outset to be reentrant, which means there is of necessity, large volumes of per-thread duplication.

Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.
"Too many [] have been sedated by an oppressive environment of political correctness and risk aversion."

In reply to Re^7: choosing threads by BrowserUk
in thread choosing threads by targetsmart

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