Hopefully we're on the same page now, though I'm getting well outside my area of personal experience (I've done threaded programming, but avoid it like the plague in Perl). IIUC switching between Perl interpreter contexts is painfully expensive, and since each queue message requires 3 switches (wait/signal/wake), that can crush you.

I haven't used them before, but isn't this a good place to apply Coro and/or Coro::EV? The Coro docs even say:

Benchmarks using i-threads which are communication-intensive show extremely bad behaviour with i-threads (in fact, so bad that Coro, which cannot take direct advantage of multiple CPUs, is often orders of magnitude faster because it shares data using real threads, refer to my talk for details).

In reply to Re^11: OT: Locking and syncing mechanisms available on *nix. by educated_foo
in thread OT: Locking and syncing mechanisms available on *nix. by BrowserUk

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