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Check now Mutex timeout



I have multiple sensors with a mutex that runs a custom exe that may take 10 seconds to execute. The timeout set to 20 seconds. I often get an error result with message "Timeout caused by wait for mutex (code: PE035)" This error frequently is presented when I "Check Now". What would cause this error? My understanding is that sensors that share a mutex are executed sequentially. Is there a limit as to how long a sensor will wait on a mutex for other sensors to execute? When one does a check now on a sensor with a mutex, does it attempt to execute immediately, or wait for the mutex? It would seem appropriate to queue the sensor to execute as soon as the mutex is next available.

mutex pe035 prtg timeout

Created on Dec 16, 2010 6:02:24 PM

Last change on Dec 21, 2010 9:55:59 AM by  Daniel Zobel [Product Manager]

4 Replies

Accepted Answer




I would strongly recommend to increase the timeout for the mutex. All sensors are executed strictly one after the other because they have to wait for the mutex to be freed. In your case—I suppose—the waiting queue gets to long and some of the sensors at the end of the line don't get get their turn.

For example: If you press "Check Now" the request immediatly gets at the end of the queue and has no more than 20 seconds to be executed. If there are allready two other sensors in the queue the request probably fails because it takes your Custom EXE 10 seconds to finish.

Best Regards.

Created on Dec 20, 2010 2:51:37 PM by  Torsten Lindner [Paessler Support]

Last change on Dec 21, 2010 9:50:21 AM by  Daniel Zobel [Product Manager]



Hey there, Does anybody know how to increase the timeout for the Exchange DAG sensors in

I am having this timeout issue on about 20 DAG sensors across 4 devices.


Created on Oct 4, 2016 11:17:44 PM



I'll talk to the developer and let you know what we find out :)

Created on Oct 5, 2016 11:21:58 AM by  Stephan Linke [Paessler Support]



According to the developer, we should rather track down the issue as the normal runtime for this sensor is about 1s, max. Is the sensor working when you have only one sensor per device?

Created on Oct 6, 2016 1:58:58 PM by  Stephan Linke [Paessler Support]

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