Why?

Because global variables have to copied for each created thread. Admittedly it's not such a big problem as with shared variables, but if you're careless they can cummulate to quite some size.

One of the reasons that perl threads aren't exactly lightweight is that there are just too many global variables (think $_ $/ $\ $, $; @ARGV  @INC ...) which all have to be copied for each created thread. And it's one of the reasons why Perl 6 tries to reduced the number of global variables wherever possible, and invents context variables instead.

Specifically @links (in the root node) looks weird to me - it's not a shared variable, but it's still a global variable (by virtue of being mentioned in sub XXX), and later declared as lexical in the main program. @queue is also global, although used only in XXX.

In reply to Re^3: Threads and LWP::UserAgent question by moritz
in thread Threads and LWP::UserAgent question by gatito

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