Topology calculation causes high CPU load after upgrading to SolarWinds Platform 2024.2, 2024.4, 2025.1 or 2025.2

The parallel topology calculation feature introduced in SolarWinds Platform 2024.2 can significantly speed up the calculation but it may also increase the CPU load. If you notice high CPU usage caused by SolarWinds.Topology.Calculator.exe or SolarWinds.Topology.Calculatorx64.exe processes, consider configuring or disabling the parallel calculation. 

Beginning in SolarWinds Platform 2025.2, the Topology Calculator runs as a 64-bit process by default.

Symptoms

• High CPU usage by SolarWinds.Topology.Calculator.exe or SolarWinds.Topology.Calculatorx64.exe
• Noticeable server performance degradation during topology calculations
• Slower response times or lag in other applications running on the same server
• CPU utilization spikes that coincide with scheduled topology calculation intervals

This issue occurs because the parallel topology calculation feature is designed to accelerate topology calculations by utilizing multiple CPU threads. However, this can significantly increase CPU load, especially on systems with many available CPU cores. Starting with SolarWinds Platform 2025.2, the Topology Calculator runs as a 64-bit process by default, which can further impact resource usage.

Resolution 1

1. Go to the Advanced Configuration page (<orion_server>/Orion/admin/advancedconfiguration/global.aspx). See Access the Advanced Configuration settings in the SolarWinds Platform Web Console.

2. In the Global tab, search for CalculationConfiguration and click the pencil icon to edit it.

3. In the Edit Setting box, search for the ProviderConfig element with the ParallelCalculationDegree key and change its value.

   • -1 - unlimited parallelization, default option.
   • 0 - disabled parallelization
   • 1..N - specific number of threads

     Note: For optimal speed and CPU usage, set the value to the number of available CPUs minus 1, leaving one CPU free for other operations. For example, if you have 8 CPUs, set the ParallelCalculationDegree value to 7.

     

4. Click OK and save your changes.

Resolution 2 

• Disable Topology Calculation if it is not needed:

  • Uncheck the TopologyEnabled setting on the Advanced Configuration page (~/orion/admin/advancedconfiguration/global.aspx)

Resolution 3

• Run Topology Calculator as a 32-bit process:
  • Uncheck the TopologyCalculation64bitEnabled setting on the Advanced Configuration page (~/orion/admin/advancedconfiguration/global.aspx):

Note: When running as a 32-bit process, the Topology Calculation may stop working due to Out-of-Memory concerns, as 32-bit processes can only use up to 2GB of RAM.

Resolution 4

• Increase Topology Calculation frequency (for example: once per day)

  • Adjust TopologyCalculationFrequency on the Advanced Configuration page (~/orion/admin/advancedconfiguration/global.aspx)

Resolution 5

• Exclude some Topology data from the calculation using the CalculationConfiguration setting on the Advanced Configuration page (~/orion/admin/advancedconfiguration/global.aspx):

  • To exclude Layer 3 Routing data, set RouteNodeDataLoader and ArpNodeDataLoader to false.

  • To exclude Layer 2 CAM / Bridge data, set BridgeNodeDataLoader and PortMapNodeDataLoader to false.

  • To exclude STP data, set StpNodeDataLoader to false.

  • To exclude CDP data, set CdpNodeDataLoader to false.

  • To exclude LLDP data, set LldpNodeDataLoader to false.