Performance Advisor returns an assertions error

When generating a report with Performance Advisor, the report fails and Performance Advisor returns an assertion error: java.lang.AssertionError.


Affected releases: Mobile Studio 2020.0.


This issue occurs when connecting to an application that is already running. Performance Advisor captures frame annotation events for a number of frames with a negative start time relative to the official start of the Streamline capture. These all get clipped to time=0, which results in an assertion for zero length frames.


Start the Streamline capture first, and then start the application. This avoids the frame events with negative start time being generated.

If this is not possible, you can disable assertions in the pa.ini file. This file is located in the Arm Mobile Studio installation directory:

On macOS, this file is located in:


Open this file in a text editor and remove the line -ea:


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