# More Tips for Executing Load Tests Please note that the underlying operating system of a single Exec Agent (load injector) can be overloaded if too many concurrent (virtual) users are executed there. In most cases where a system is overloaded, the CPU(s) of the Exec Agent will be constantly at nearly 100% used. In these cases, the measured response times will not be valid **because the measuring system itself is overloaded**. We recommend that you monitor the CPU consumption of the Exec Agent during the load test and that you use an **Exec Agent** [**Cluster**](https://apica-kb.atlassian.net/wiki/spaces/DAZT/pages/4620499/Clusters), instead of a single Exec Agent when a single system does not have the necessary CPU resources to properly generate the load. The CPU consumption of the load-releasing system depends on the number of users (more users Furthermore, we recommend that you tune the TCP/IP parameters of load releasing systems. --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://docs.apica.io/platform-docs/zebratester-scripting/zebratester-user-guide/4.-execute-the-load-test/executing-load-test-programs/more-tips-for-executing-load-tests.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.