Ben Franksen
Spencer Janssen wrote:
On Sun, Jan 06, 2008 at 11:30:53AM +0000, Andrew Coppin wrote:
1. Is there some way to assign a "priority" to Haskell threads? (The behaviour I'd like is that high priority threads always run first, and low priority threads potentially never run at all unless there's an available processor which is completely idle.)
Not in the current system. It is not clear that thread priorities are so nice anyway (see 'priority inversion' on Wikipedia, for example).
As the wikipedia page also mentions well-known counter-measures, such as priority inheritance and priority ceilings. For real-time applications, priorities are a /must have/. Or at least, I can't see anything nicer that could replace them.
Preemption, for hard real-time. For soft real-time, yes, SCHED_FIFO and SCHED_RR are a must. -- (c) this sig last receiving data processing entity. Inspect headers for past copyright information. All rights reserved. Unauthorised copying, hiring, renting, public performance and/or broadcasting of this signature prohibited.