Testing in Parallel

The UiAutomator2 driver supports running multiple sessions in parallel. This can be implemented in two ways:

• Multiple Appium server processes with a single session each
• Single Appium server process with multiple sessions (uses less resources and ensures better control over running sessions)

Note that a single device under test should only be used in one session at a time.

Tip

If testing in parallel is not required, consider enabling the --session-override Appium server flag, which ensures deletion of all existing sessions when a new one is started.

Important Capabilities

In order to avoid issues when running parallel sessions, several capabilities should be explicitly specified in each session, and must have a unique value among all parallel sessions:

• appium:udid - for real devices
• appium:avd - for emulators
• appium:systemPort
• appium:chromedriverPort - if using hybrid/webview mode
• appium:mjpegServerPort - if using MJPEG streams