unix-internal anybody?

[Godmar Back]

> 
> Godmar Back writes:
> 
> QNX 4 doesn't support ITIMER_VIRTUAL timers, and consequently cannot
> use jthreads as is. Would it be possible to let jthreads default to
> non-preemptive scheduling when ITIMER_VIRTUAL is not defined? In that
> case QNX 4 could use jthreads. 
> 

Currently, jthreads assumes that ITIMER_VIRTUAL works if HAVE_SETITIMER
is defined.  See the #if defined(HAVE_SETITIMER) surrounding the
activate_time_slicing/deactivate_time_slicing definitions.

It's already defaulting to non-preemptive scheduling if setitimer isn't 
there.  We can certainly add a && defined(ITIMER_VIRTUAL) is that will
do.  Plus, we may want to exclude the call to catchSignal(SIGVTALRM) too.

	- Godmar

> 
>  > 
>  >  Is anybody still relying on the old, non-preemptive internal threading
>  > system (i.e. you configure with --with-threads=unix-internal)?
>  > 
>  > This would be the case for systems that do not provide support for
>  > asynchronous/non-blocking I/O.
>  > 
>  > It will be nuked soon from the CVS repository.  However, if people depend
>  > on the ability to use kaffe on systems that do not provide support for
>  > asynchronous I/O, we could integrate this ability in the unix-jthreads code.
>  > 
>  > 	- Godmar
>  > 
> 
>