High CPU usage on the Filtering Service machine

When the CPU on the Filtering Service machine is overloaded (whether by the volume of processing being performed by Filtering Service, or by demands from other software running on the Filtering Service machine), users may experience slow browsing, as requests for sites take longer to process.

During times of peak CPU usage (exceeding 95%), Filtering Service may be unable to process requests at all, leading to incorrect policy enforcement.

To address this issue, start by using the Task Manager (Windows) or top command (Linux) to determine which processes on the machine are causing CPU usage to peak.

• Are there applications that could be run from another machine?
• Can you move Filtering Service to a dedicated machine?

If Filtering Service is using a high amount of processing time:

• Evaluate the amount of traffic being processed by Filtering Service. DNS lookups can require a fair amount of processing time; you may want to install an additional Filtering Service instance for load balancing.
• Evaluate your use of keywords and regular expressions. Are you using a large number of regular expressions or keywords, or using very complex regular expressions?

Reducing the number of keywords and regular expressions, or removing or simplifying complex regular expressions can improve Filtering Service performance.