YongQin Liu <yongqin.liu@linaro.org> writes:

> Hi, Andy & Michael
>
>
> About the problem that the telnet process consumes

> CPU(bug1034218<https://bugs.launchpad.net/linaro-android/+bug/1034218>
> ),

> For now I tried two ways to verify it:
> 1. Run the CTS test via submitting a lava-job
>     In this way, the process that consumes CPU is telnet
> 2. Run the CTS test via command line "lava-android-test run cts"
>     In this way, there is no process that consumes CPU to 100%,
>     In the meanwhile, I also opened the telnet session.
>
> So I guess the problem is the way we calling the telnet command in
> lava-dispatcher.
> From my investigation, it's the select syscall in telnet that consumes CPU,
> So I doubt if there is some place in lava-dispatcher that reads the ouput
> of telnet in a loop without sleep in the loop.
> but I did not find such place in lava-dispatcher.
>
> How do you think about it?

This is all fairly strange.  However, it seems like this is not the
problem we had running CTS before; IIRC then it was java processes
causing trouble on control.  As the load from telnet is pure CPU load
(i.e. it doesn't consume masses of RAM or do loads of IO) I would be in
favour of enabling CTS again (carefully) and watching the graphs on
http://munin.validation.linaro.org/validation.linaro.org/control.validation.linaro.org/index.html

Cheers,
mwh