High CPU usage at idle

Hi,

Can anyone please confirm if 7% cpu usage for rioboard_d is normal when nothing else is running? This is clean install with only rioboard_d started, no test apps etc.



root 763 6.8 0.1 3300 660 ? Ss 14:41 35:20 rioboard_d start

Linux alarmpi 3.12.24-1-ARCH #1 PREEMPT Thu Jul 10 23:57:15 MDT 2014 armv6l GNU/Linux

wiringpi2

Hello karman,

Yes - I confirm that. CPU usage is around 7% (Raspbian, fresh install + WiringPi).

The reason for this is rather intensive poling of SPI in order to grab RIOBoard's IO readings as close as possible to real time and map over shared memory for API to get (on user's demand yes, but the data should be there by that demand moment of time).

Do you think this would be an obstacle for your application?

Opal,

Thanks.

I think its nice setup for 99% of systems, but our system are solar powered so we need as little as possible load to reduce consumption (in theory). I checked the code and won't be issue just to poll the Rio directly in our program.

The plan is to do most of the logic in microbasic (If I'm able to somehow get to transfer the code to rio) and only get stats from Rio and post to web service via the raspberry. We only need stats about every 30 seconds for historic logging.

L:

Hello karman,

I checked the code and won't be issue just to poll the Rio directly in our program.

Hm ... despite that this approach is absolutely valid and technically rather straightforward one, we would recommend to stick to our API (who knows what the next updates could bring in the near future).

What if we provide some means to adjust the poling intensity (say, as a parameter of Init() function)? Would it do the job?