Re: [Xenomai-help] Very high latencies under stress testing

[edward.robbins@domain.hid]

>>
>> CRID, disabled memory thermal management, turned off lots of ACPI and
> 
> Pay attention not to disable ACPI completely, as this enables APM, the
> legacy power management, and this one causes high latencies.
> 

I'm pretty sure it's still enabled.

>>
>> I'm at a bit of a loss. Next I will try to figure out how to read the
>> traces. The latency consistently jumps from <20us (normally around
>> 14/15) to just under 4500us each time I run the test, so I am
>> wondering if it is some specific thing that takes this long. I will
>> also try to read the LTP output to see what it's doing when it fails,
>> and see if this is consistent.
>>
>> Gilles, I really appreciate all the help, thank you.
> 
> You are welcome, no problem. A few things to try: could you try and use
> the latest I-pipe for 2.6.35? Just to rule out anything which would have
> been fixed since 2.6.32.
> 

I did wonder if I should do this. I'll try that next, though I'm not sure when that will be.

> Something else, did you try to run your system completely without
> framebuffer and X-window? In good old text mode?
> 

Yes, all these tests are with X disabled, I'm not even using framebuffer just straight console mode.

> I do not know what more to suggest. The traces you sent show
> consistently ipipe_check_context at the point where you have the issue,
> I do not know whether this is a coincidence. Do you get any I-pipe
> message in the kernel logs after the latency peak happens?
> 
I'm fairly sure the answer is no, but will have to double check next time I'm working on the system.