View Anomalies: CPU Load

markrrichardson · September 5, 2021, 11:15am

How is the CPU Load calculated? I get this error:

CPU load of 100% is fairly high. You might consider running fewer programs on your Pi, or upgrading your Pi to a faster version such as the Pi 2.

I have a Pi 3B+. When i check the cpu load, it’s not 100%. Graphs 1090 never shows a load that high. Is that just for 1 core? Or is the CPU load something else entirely different?

Also, feeding 2 sites with just the one Pi. Shouldn’t i see the error for both sites since it’s the same Pi?

obj · September 5, 2021, 11:24am

github.com

flightaware/piaware/blob/master/package/fa_sysinfo.tcl#L43


      
          		}
          
          
		return [expr {$result / 1000.0}]
          	}
          
          
	#
          	# cpu_load - return the cpu load since the last call (or since boot if no previous call)
          	# as a percentage (0-100)
          	#
          	variable lastCPU [list 0 0]
          	proc cpu_load {} {
          		variable lastCPU
          
          
		lassign [cpu_ticks] load_ticks elapsed_ticks
          		lassign $lastCPU last_load_ticks last_elapsed_ticks
          
          
		set recent_load 0
          		if {$elapsed_ticks > $last_elapsed_ticks} {
          			set recent_load [expr {round(100.0 * ($load_ticks - $last_load_ticks) / ($elapsed_ticks - $last_elapsed_ticks))}]
          		} else {
          			set recent_load 0

(tl;dr: it’s a total across all cores)

I don’t see any CPU problems currently reported for either of your sites.

FIRE5IGN · October 19, 2021, 2:28pm

I’m interested in this question also. I’m running an RPi Zero; I have turned off A/C decoding and set low-cpu to yes. Yet I’m getting the CPU load anomaly. When I log in via SSH and run top, this is what it reports:

top - 14:15:08 up  2:24,  1 user,  load average: 0.50, 0.60, 0.70
Tasks:  83 total,   2 running,  80 sleeping,   1 stopped,   0 zombie
%Cpu(s): 42.8 us, 12.6 sy,  0.0 ni, 41.9 id,  0.0 wa,  0.0 hi,  2.7 si,  0.0 st
MiB Mem :    430.0 total,    282.8 free,     52.5 used,     94.7 buff/cache
MiB Swap:      0.0 total,      0.0 free,      0.0 used.    324.8 avail Mem

Why am I receiving this anomaly when top reports an average load of roughly 60%?