Re: [patch] Real-Time Preemption, -RT-2.6.12-rc3-V0.7.46-01

Inaky Perez-Gonzalez
2005-04-22T21:06:42Z

>>>>> Ingo Molnar <mingo@elte.hu> writes:

>> this includes fixes from Daniel Walker, which could fix the plist
>> related slowdown bugs:

> there are still some problems remaining: i just ran Esben Nielsen's
> priority-inheritance validation testsuite, and the plist code gives
> a worst-case latency of 9.0 msecs.

With which machine is this?

I tried to reproduce with V0.7.45-01 in my 2xPIII 0.9 Ghz I cannot get
more than 1.9ms when doing 2000 samples repeatedly (60 iterations and
counting).

Did you use other parameters to 'test'?

# cnt=0
# while true
> do echo -n "$cnt "
> ./test --samples 2000 file.hist 2>&1 | grep maximum; cnt=$(($cnt+1))
> done

With 2.6.12-rc3-V0.7.46-02 I get:

...
2 maximum cycle time: 0.003ms
3 maximum cycle time: 1.706ms
4 maximum cycle time: 1.538ms
5 maximum cycle time: 1.168ms
6 maximum cycle time: 0.003ms
7 maximum cycle time: 0.008ms
8 maximum cycle time: 1.821ms
9 maximum cycle time: 1.013ms
10 maximum cycle time: 1.043ms
11 maximum cycle time: 1.787ms
12 maximum cycle time: 1.519ms
13 ...

roughly the same as with 0.7.45-01:

0 maximum cycle time: 1.872ms
1 maximum cycle time: 0.008ms
2 maximum cycle time: 1.947ms
3 maximum cycle time: 1.902ms
4 maximum cycle time: 1.925ms
5 maximum cycle time: 0.002ms
6 maximum cycle time: 1.950ms
7 maximum cycle time: 0.008ms
8 maximum cycle time: 0.008ms
9 maximum cycle time: 0.008ms
10 maximum cycle time: 1.943ms
11 maximum cycle time: 1.173ms
12 maximum cycle time: 0.008ms
13 maximum cycle time: 0.008ms
...

--

Inaky