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[[!tag open_issue_hurd]]

Hurd servers / VFS libraries are multithreaded.


# Implementation

  * well-known threading libraries

      * [[hurd/libthreads]]

      * [[hurd/libpthread]]


# Design

Roughly using one thread per
incoming request.  This is not the best approach: it doesn't really make sense
to scale the number of worker threads with the number of incoming requests, but
instead they should be scaled according to the backends' characteristics.

The [[hurd/Critique]] should have some more on this.

[*Event-based Concurrency
Control*](http://soft.vub.ac.be/~tvcutsem/talks/presentations/T37_nobackground.pdf),
Tom Van Cutsem, 2009.


# Alternative approaches:

  * <http://www.concurrencykit.org/>

  * Continuation-passing style

      * [[microkernel/Mach]] internally [[uses
        continuations|microkernel/mach/continuation]], too.

  * [[Erlang-style_parallelism]]

      * [[!wikipedia Actor_model]]; also see overlap with
        {{$capability#wikipedia_object-capability_model}}.

  * [libtcr - Threaded Coroutine Library](http://oss.linbit.com/libtcr/)

  * <http://monkey.org/~provos/libevent/>

---

See also: [[multiprocessing]].