Averaging temperature within a nested loop - powershell

Question

I'm trying to write a script that fetches the CPU temperature using OpenHardwareMonitor and will alert if it averages above a certain threshold over a given duration.
Getting the current temperature is working perfectly, but I'm struggling to average them out because on some systems there may be one or more CPU so I can't just log the temperature every minute and divide by how many minutes have passed, below is the best I've got (that doesn't work), please could some kind soul help me see where I'm going wrong?
$tempThreshold = 80 # Will alert if average temperature is above this
$minutes = 3 # Duration in minutes to test for
start-process "$env:SystemRoot\TEMP\OpenHardwareMonitor\openhardwaremonitor.exe"
# Loop each minute
for ($i=1; $i -le $minutes; $i++) {
$arrSensors=#{}
if ((Get-WmiObject -Namespace "Root\OpenHardwareMonitor" -Query "SELECT * FROM Sensor WHERE Sensortype='Temperature'" | ? {$_.Name -match 'CPU Package'}).value) {
Get-WmiObject -Namespace "Root\OpenHardwareMonitor" -Query "SELECT * FROM Sensor WHERE Sensortype='Temperature'" | ? {$_.Name -Match "CPU Package"} | % {$arrSensors[$_.Name]=$_.Value}
} else {
Get-WmiObject -Namespace "Root\OpenHardwareMonitor" -Query "SELECT * FROM Sensor WHERE Sensortype='Temperature'" | ? {$_.Identifier -match 'cpu/'} | % {$arrSensors[$_.Name]=$_.Value}
}
$temps = foreach ($sensor in $arrSensors.getEnumerator()) {
Start-Sleep -Seconds 60
$temp = $temp+$sensor.value
}
}
# Alert if average above threshold
if ($temps/$minutes -gt $tempThreshold) {
Write-Host "Alert function here"
}

Answer 1

i was also looking for monitoring cpu temperature on windows. my backend was grafana with an influxdb. using ohm and wmi was very cpu intense and i found https://github.com/nickbabcock/OhmGraphite#influxdb-configuration. this app is based on ohm but sends the data directly to the influxdb (no expensive wmi-calls needed). maybe this is also of interest for you. using grafana you could average the value and set a threshold there.
but - maybe that is not an option for you so here the script to get the average using the ohm application.
the downside of this script is, that the script runs for 2 minutes - so you won't get the alert every minute (unless you run it twice with a minute appart (which could be easily setup using scheduled tasks).
$tempThreshold = 80 # Will alert if average temperature is above this
$minutes = 3 # Duration in minutes to test for
start-process "$env:SystemRoot\TEMP\OpenHardwareMonitor\openhardwaremonitor.exe"
$counter = 0
$sum = 0
while($counter -lt $minutes) {
$cpuArray = Get-WmiObject -Namespace "Root\OpenHardwareMonitor" -Query "SELECT * FROM Sensor WHERE Sensortype='Temperature'"
if($cpuArray | where name -like 'cpu package*') {
$cpuTempArray = $cpuArray | where name -like 'cpu package*'
} else {
$cpuTempArray = $cpuArray | where name -like 'cpu core*'
}
foreach($cpuTemp in $cpuTempArray){
$sum += $cpuTemp.value
}
$counter++
if($counter -ne $minutes) {
Start-Sleep -Seconds 60
}
}
$average = $sum/($counter*$cpuTempArray.Count)
# Alert if average above threshold
if($average -gt $tempThreshold) {
Write-Host "Alert function here"
}

Answer 2

as mentioned my other answer the other script runs once and IMHO cannot be seen as "monitoring" - as in 'alert whenever the threshold is hit' - like ever minute.
the following script runs in an endless loop. it collects the set amount of data ($minutes) as average of every minutes. you might wanna change this to store the max value of all cpus in the $valueArray and then take the average of this.
$tempThreshold = 80 # Will alert if average temperature is above this
$minutes = 3 # Duration in minutes to test for
Start-Process -FilePath "$env:SystemRoot\TEMP\OpenHardwareMonitor\openhardwaremonitor.exe"
$valueArray = [System.Collections.ArrayList]#()
while($true) {
# keep only #no of values in array specified in $minutes
if($valueArray.Count -gt $minutes) {
# remove oldest entry from array
$valueArray.RemoveAt(0)
}
if($valueArray.Count -eq $minutes) {
$average = ($valueArray | Measure-Object -Sum).Sum/$minutes
# Alert if average above threshold
if($average -gt $tempThreshold) {
Write-Host "Alert function here"
}
}
$sensorArray = Get-WmiObject -Namespace "Root\OpenHardwareMonitor" -Query "SELECT * FROM Sensor WHERE Sensortype='Temperature'"
if($sensorArray | where name -like 'asdf cpu package*') {
$cpuTempArray = $sensorArray | where name -like 'cpu package*'
} else {
$cpuTempArray = $sensorArray | where name -like 'cpu core*'
}
$counter = 0
$sum = 0
foreach($cpuTemp in $cpuTempArray) {
$counter++
$sum += $cpuTemp.value
}
$currentAverageTemp = $sum/$counter
$valueArray.Add($currentAverageTemp)
Start-Sleep -Seconds 60
}