Advice on configuring Controller / Agents before running a large load test
Use the latest version of Silk Performer.
- Minimize traffic between the agent-controller:
- In the monitor window of Silk Performer set the Data collection interval of the monitor to "Manually".The default setting for this is 5 sec. To check status during the loadtest click the Refresh Now button.
- De-select the button "Display all Errors of all Users" in the Toolbar of the monitor window . By default this is selected.
- Do not check "Show output of WebUser..." in the context menu of the virtual user view of the monitor window during. By default this is not checked.
- Add additional network cards to agents (ensure all cards are set to full duplex) - see "Performance and Scalability Matrix" in Help.
- Optimize Performance Explorer to minimize communications during the loadtest. Do not monitor the Silk Performer Controller data source (Active users, Transaction Rate, Hits/s etc). By default these are monitored. To stop monitoring you can choose Remove Data Source from the context menu in Performance Explorer.
- Ensure the "Virtual Users per Process" is set to"Automatic"(SETTINGS | SYSTEM | WORKBENCH | CONTROL -Virtual Users)
- Stop all unnecessary processes running on controller / agents -this may include automatic "Windows updates".
- Machine specification: Despite the trend for multiple processor machines - the common loadtest bottleneck on the windows platform is I/O, so instead of using a single 8 processor machine and running all users on 1 machine it is recommended instead to use 3 or 4 "normal" 1 or 2 processor boxes.
Finally reboot the machines before starting the test to ensure that you are starting with no baggage, and that any Windows updates have taken affect.