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[nptl] Re: SCHED_RR issue



> Anyway, what we see is not FAIL but the sample will timeout after 30
> > seconds. 
> 
> Do you see that behavior, even after fixing the for(...) loop in the 
> HP threads? 

Oooops I'm sorry, I felt into another bug: as a normal user, the pthread_create() call hangs for me :/ I don't know why...

I started again as root and now it's just falling back to the initial situation:
-> With NCPU small (6 for a 2-way box), the test just fails.
-> With NCPU big (128 for a 2-way box), the test timeouts.

(*) I removed the for(i:1->10000000) ; loop
(*) I added a semaphore to make sure the HP are running.

The new file is attached to this mail & uploaded in the forum soon.





On Tue, 2004-09-07 at 18:20, Loic Domaigne wrote:
> Hello Sebastien, 
> 
> > I now understand the problem in my test why it should report FAIL even
> > in a working scheduler, in the range of the POSIX spec. 
> 
> YES.
> 
> > I'll have to modify the sample in order to make sure every thread 
> > really started -- for exemple by posting a semaphore in each threads, 
> 
> YES. Something similar. 
> 
> 
> > but I need some more checking for this yet.
> 
> I spoke with Steve Watt, a kernel programmer of the RTOS LynxOS
> (that you met on c.p.t. already, BTW). He confirms that, 
> from its understanding, the behavior is unspecified.
> See his answer in attachment. 
> 
> 

> Strange! To my understanding, the timeout did occurred simply because
> the computation weren't finished yet... I have to check your new test in
> more extend, and try to reproduce the behavior on my machine I guess...
> 
> Cheers,
> Loic.
-------------------------------
Sebastien DECUGIS
NPTL Test & Trace Project
http://nptl.bullopensource.org/

"You may fail if you try.
You -will- fail if you don't."

sched_rr.c.gz