[Xenomai-help] Is such latency normal?

[Xenomai-help] Is such latency normal?

[Sergey PENIAZ]

Hello,

I'm novice at xenomai. I just builded xenomai for platform based on "Intel(R) 
Pentium(R) 4 CPU 1500MHz". And I obtained next latency values. Are such 
values normal for this cpu? Or maybe is there a way to decrease them? 

testpc:/usr/xenomai/bin# ./cyclictest -i 200 -p99 -t 5
0.02 0.02 0.00 1/70 3272

T: 0 ( 3268) P:99 I: 200 C: 59941 Min: 2 Act: 12 Avg: 8 Max: 21
T: 1 ( 3269) P:98 I: 700 C: 17126 Min: 3 Act: 8 Avg: 11 Max: 35
T: 2 ( 3270) P:97 I: 1200 C: 9991 Min: 9 Act: 20 Avg: 15 Max: 43
T: 3 ( 3271) P:96 I: 1700 C: 7052 Min: 3 Act: 8 Avg: 13 Max: 52
T: 4 ( 3272) P:95 I: 2200 C: 5450 Min: 12 Act: 13 Avg: 17 Max: 61

-- 
With Best Regards
Sergey Peniaz
Visutech System Ltd.

E-Mail:Sergey.Peniaz@domain.hid

Re: [Xenomai-help] Is such latency normal?

[Gilles Chanteperdrix]

Sergey PENIAZ wrote:
> Hello,
> 
> I'm novice at xenomai. I just builded xenomai for platform based on "Intel(R) 
> Pentium(R) 4 CPU 1500MHz". And I obtained next latency values. Are such 
> values normal for this cpu? Or maybe is there a way to decrease them? 
> 
> testpc:/usr/xenomai/bin# ./cyclictest -i 200 -p99 -t 5
> 0.02 0.02 0.00 1/70 3272
> 
> T: 0 ( 3268) P:99 I: 200 C: 59941 Min: 2 Act: 12 Avg: 8 Max: 21
> T: 1 ( 3269) P:98 I: 700 C: 17126 Min: 3 Act: 8 Avg: 11 Max: 35
> T: 2 ( 3270) P:97 I: 1200 C: 9991 Min: 9 Act: 20 Avg: 15 Max: 43
> T: 3 ( 3271) P:96 I: 1700 C: 7052 Min: 3 Act: 8 Avg: 13 Max: 52
> T: 4 ( 3272) P:95 I: 2200 C: 5450 Min: 12 Act: 13 Avg: 17 Max: 61

The latencies of other threads than the one which runs with the highest
priority are not all that significant, so, the only figure which matters
is 21us. It does not seem that bad.

However, notice than when running cyclictest or latency, you should
apply a load of some sort, such as dd, ping flood, calibrator, etc...

Also, did you check SMIs?

-- 
                                                 Gilles.

Re: [Xenomai-help] Is such latency normal?

[Sergey PENIAZ]

Thanks for you help. 

> Also, did you check SMIs?
Do you mean this?

testpc:/usr/src/linux-2.6.26.8# cat .config | grep SMI
# SMI workaround
# CONFIG_XENO_HW_SMI_DETECT_DISABLE is not set
CONFIG_XENO_HW_SMI_DETECT=y
# CONFIG_XENO_HW_SMI_WORKAROUND is not set



On 6 March 2009, Gilles Chanteperdrix wrote:
> Sergey PENIAZ wrote:
> > Hello,
> >
> > I'm novice at xenomai. I just builded xenomai for platform based on
> > "Intel(R) Pentium(R) 4 CPU 1500MHz". And I obtained next latency values.
> > Are such values normal for this cpu? Or maybe is there a way to decrease
> > them?
> >
> > testpc:/usr/xenomai/bin# ./cyclictest -i 200 -p99 -t 5
> > 0.02 0.02 0.00 1/70 3272
> >
> > T: 0 ( 3268) P:99 I: 200 C: 59941 Min: 2 Act: 12 Avg: 8 Max: 21
> > T: 1 ( 3269) P:98 I: 700 C: 17126 Min: 3 Act: 8 Avg: 11 Max: 35
> > T: 2 ( 3270) P:97 I: 1200 C: 9991 Min: 9 Act: 20 Avg: 15 Max: 43
> > T: 3 ( 3271) P:96 I: 1700 C: 7052 Min: 3 Act: 8 Avg: 13 Max: 52
> > T: 4 ( 3272) P:95 I: 2200 C: 5450 Min: 12 Act: 13 Avg: 17 Max: 61
>
> The latencies of other threads than the one which runs with the highest
> priority are not all that significant, so, the only figure which matters
> is 21us. It does not seem that bad.
>
> However, notice than when running cyclictest or latency, you should
> apply a load of some sort, such as dd, ping flood, calibrator, etc...
>
> Also, did you check SMIs?



-- 
With Best Regards
Sergey Peniaz
Visutech System Ltd.

E-Mail:Sergey.Peniaz@domain.hid

Re: [Xenomai-help] Is such latency normal?

[Gilles Chanteperdrix]

Sergey PENIAZ wrote:
> Thanks for you help. 
> 
>> Also, did you check SMIs?
> Do you mean this?
> 
> testpc:/usr/src/linux-2.6.26.8# cat .config | grep SMI
> # SMI workaround
> # CONFIG_XENO_HW_SMI_DETECT_DISABLE is not set
> CONFIG_XENO_HW_SMI_DETECT=y
> # CONFIG_XENO_HW_SMI_WORKAROUND is not set

I mean, did you read the TROUBLESHOOTING guide and applied what you
found there ?

-- 
                                                 Gilles.

Re: [Xenomai-help] Is such latency normal?

[Sergey PENIAZ]

Yes.

Thanks.

On 6 March 2009, Gilles Chanteperdrix wrote:
> Sergey PENIAZ wrote:
> > Thanks for you help.
> >
> >> Also, did you check SMIs?
> >
> > Do you mean this?
> >
> > testpc:/usr/src/linux-2.6.26.8# cat .config | grep SMI
> > # SMI workaround
> > # CONFIG_XENO_HW_SMI_DETECT_DISABLE is not set
> > CONFIG_XENO_HW_SMI_DETECT=y
> > # CONFIG_XENO_HW_SMI_WORKAROUND is not set
>
> I mean, did you read the TROUBLESHOOTING guide and applied what you
> found there ?


-- 
With Best Regards
Sergey Peniaz
Visutech System Ltd.

E-Mail:Sergey.Peniaz@domain.hid