Re: Thread library for ocamlopt?

[Thorsten Ohl <ohl@crunch.ikp.physik.th-darmstadt.de>]

Xavier Leroy <Xavier.Leroy@inria.fr> writes:

> We have such an implementation of Caml threads for Win32
> (bytecode only).  Some work is in progress to extend it to
> Posix threads and to the native-code compiler.

This is good news and I'm looking forward to it!

> * Available only on Unix systems that provide fully conformant
> Posix 1003.1c threads, e.g. Solaris 2.5, Digital Unix 4.0, or
> Linux with LinuxThreads, but not HPUX, SunOS, nor earlier
> versions of Digital Unix, for instance.

Couldn't the implementation on the latter three OSs emulate the
semantics (without the performance benefit, of course) with the old
threads?  Then programs would remain portable and users of
multiprocessor machines running the former three OSs could start
chasing around the FORTRAN crowd :-).

> * Preemption of long-running threads can only occur at
> allocation points (for reasons relevant to both the garbage
> collector and the handling of signals in ocamlopt), which can
> result in a relatively rough scheduling for compute-bound
> threads.

By your high standards it will be considered a nasty hack, but what
will prevent us users from adding spurious allocation points, if the
scheduling turns out to be too rough in a practical case?

Cheers,
-Thorsten
-- 
Thorsten Ohl, Physics Department, TH Darmstadt --- PGP: AF 38 FF CE 03 8A 2E A7
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