Agent FAQ

Traffic & Load

Important

How often do PerformanceGuard agents communicate with the server?

The PerformanceGuard agent will open and send aggregated performance data to PerformanceGuard through a normal TCP/IP connection at every delivery interval. The delivery interval is 180 seconds (that is three minutes) by default, but can be adjusted to any value in the range 1-30 minutes. To adjust the delivery interval in the PerformanceGuard web interface, select ADMINISTRATION > Setup > Parameters > Status and change the DELIVERY_INTERVAL setting. You can only do this if you’re a PerformanceGuard administrator.

Important

How much data is transferred across the network from agents to the server?

On average, 3,6 KB of data is transferred from a single agent on an end user computer to PerformanceGuard at every delivery. That’s the equivalent of 20 bytes per second. The amounts may of course vary depending on user behavior and your configuration, but our customers generally find that PerformanceGuard traffic is completely negligible compared to other traffic.

Important

How much load do agents put on the computers on which they are installed?

For end-user computers the PerformanceGuard agent will use much less than 1% on average of the total available CPU. For PerformanceGuard agents running on Citrix servers a higher CPU consumption of nearly 1% can occur, especially if a lot of transaction filters are enabled, and the server has a lot of HTTP traffic to the servers in the filter.

Important

We Use Citrix. How much Citrix latency data is transferred across the network from agents to the server?

On average, 400 bytes are transferred from a single session on a Citrix server to PerformanceGuard at every delivery. With 50 concurrent sessions on a Citrix server, approximately 110 bytes/sec (total) are transferred from the agent to server. This may vary depending on user behavior and your configuration.

Post-Installation

Important

I've just installed an agent. I want to view startup data from the agent in PerformanceGuard. How can I speed up that process?

Because the computer doesn’t need to be restarted when you install the agent, it can take a while before you get startup data from the agent. You can of course restart the computer in order to speed up the process, but for technical reasons you should wait at least ten minutes after installing the agent before you restart the computer.

Important

Why can't I see the agent icon in my computer's task bar?

Nowadays the agent icon is by default not shown. For more information, see the troubleshooting section on Agent Icon Is Missing.

Agent-Server Connection

Important

Why won't agents connect to the server, even though the server is online?

See the troubleshooting section in Agent Can’t Connect.

Important

What happens if an agent can't connect to the server?

The agent retries for every delivery interval (by default every 180 seconds). For every five retries, it clears its collected data to avoid accumulating too much data that could eventually lead to memory problems.

Version

Important

How can I find out if all of my organization's computers run the latest agent version?

Use the Computer Overview and remember to click the overview’s Export button to view exactly which computers run which agent versions.

Targeted Monitoring

Important

How do I limit my agents so that they only monitor traffic to and from selected servers?

Use a Berkeley Packet Filter. See Agent Configuration > Network Report in Agent Configuration Group Settings. You can only do this if you’re a PerformanceGuard administrator.

Environment

Important

Can the agent co-exist with applications that use WinPCap, for example Wireshark?

Yes, but if you run the agent and WinPCap on a 64-bit computer, you should read Agents and Wireshark / WinPCap.

Important

Why can't my agent read 32-bit performance counters?

This can happen in mixed 32-/64-bit environments, for example if the PerformanceGuard agent that should read 32-bit dll-based performance counters is a 64-bit agent. To solve this problem, do the following on the computer that runs the agent: Select /Start, type services.msc and press ENTER. Then right-click the service Performance Counter DLL Host, select Properties, set Startup type to Automatic, start the service, and click OK. This will make 32-bit counters available in 64-bit applications. Finally, restart the PerformanceGuard Agent service.

Errors

Important

Why are agent network IP traffic measurements incorrect or missing?

If you have an intelligent network interface card, and the Windows option TCP Offload Engine is enabled on the computer, the agent can’t see all the network traffic. Solution: Disable the TCP Offload Engine option.