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Processor Buffer Full?



This notice is one I don't recall seeing previously. How best to correct?

Ticket #1687: The flow processor buffer is full. The reason might be that PRTG is not able to process the flows. To resolve this issue, consider using remote probes. Also reduce the filtering and toplist parameter

buffer filtering prtg

Created on Apr 20, 2021 2:07:45 PM

Last change on Apr 20, 2021 2:56:02 PM by  Felix Wiesneth [Paessler Support]

2 Replies




It would seem PRTG is not able to process all flows. Please have a look here for further information.

How many flow sensors are you using? We recommend to use less than 50 flow sensors per probe. Also this issue does not only depend on the traffic itself, but also on the filters and toplists being used. Check if the behavior persists if you reduce the filtering/toplist parameters or increase the scanning intervals.

Created on Apr 22, 2021 1:24:10 PM by  Timo Dambach [Paessler Support]

Last change on Dec 2, 2021 10:23:02 AM by  Maike Guba [Paessler Support] (2,404) 2 1



I am using 27 sensors in Netflow. Oddly the notices have stopped and I have not made any changes.

Created on Apr 23, 2021 11:41:20 AM

Disclaimer: The information in the Paessler Knowledge Base comes without warranty of any kind. Use at your own risk. Before applying any instructions please exercise proper system administrator housekeeping. You must make sure that a proper backup of all your data is available.