Re: GNAT 3.14 NEW FEATURES LIST Current as of May 30th, 2001

[Thierry Lelegard <thierry.lelegard@canal-plus.fr>]

> The only other compatability issue I saw in that (huge) list of chages was that
> they are changing the default Linux thread library to native instead of FSU. I
> can see arguments either way on that one.

Tha major issue with FSU threads is that they are unknown to the kernel
and any I/O is blocking for the whole process. Any single Text_IO.Get_Line
or socket read blocks all tasks in the application. This very unlikely
the kind of behavior one would expect from a multi-tasking Ada application.

Using the native threads removes the problem.

The only reason for using FSU thread is the full respect of RM tasking
semantic. In the real world, applications make I/O and I suppose that the
number of applications which need the precise tasking semantic but can
afford blocking I/O's is quite small...

-Thierry
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Thierry Lelegard, "The Jazzing Troll", Email: thierry.lelegard@canal-plus.fr
CANAL+ Technologies, 34 place Raoul Dautry, 75906 Paris Cedex 15, France
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