1. A distributed testing framework, comprising: at least one processor; one or more test schedulers; a plurality of agent machines using virtualization to run one or more guest operating systems; one or more web client applications that are run in the guest operating systems on the agent machines, the one or more web client applications execute tests scheduled by a test scheduler of the one or more test schedulers, and the one or more web client applications communicate with one or more networked servers during test execution; an application layer data collecting subsystem, at an agent machine, that collects application layer data related to test execution for a web client application; a network layer data collecting subsystem, at the agent machine, that collects network layer data related to interaction during test execution between the web client application and the one or more networked servers; a data storing subsystem that stores the application layer data and the network layer data; and wherein the stored application layer data and the stored network layer data are aggregated and presented to a user via a user-interface subsystem; wherein the application layer data collection subsystem operates in the guest operating system that is running on the agent machine, and the network layer data collection subsystem operates in a host operating system of the agent machine.