Mozilla Launches Firefox Android Telemetry Investigation

TapTechNews on May 31st, Mozilla officially announced the launch of an investigation program for the Android version of the Firefox browser to analyze the impact of Telemetry on the browser's performance.

According to user feedback, after enabling Telemetry on the Android version of the Firefox browser, it not only affects the loading of websites, but also affects the startup of the browser.

For example, the test results on CNN show that the time to call the CPU to load the page increased by 16.5 seconds after enabling Telemetry.

TapTechNews translated the content of Mozilla's official reply as follows:

This means that there will be a large number of writes on the device disk in various situations such as page loading, scrolling, video playing, startup, etc.

For example, we observed hundreds of writes per second during scrolling (before the bug 1898515 closed resulting in most of the updated metrics), and there were ~32000 writes when loading cnn.com.

On the Pixel6 we tested, each write takes about 0.5 milliseconds of CPU time, so loading cnn.com requires an additional 16.5 seconds of CPU time.

In addition, in terms of testing the startup of the browser, the CPU occupation time was 25 seconds when Telemetry was closed, and it reached 35 seconds when it was enabled, which was 40% more time.

Mozilla found the reason why Telemetry increases the overhead of the browser. The core reason is that the writes to the Telemetry database are not grouped, and whenever there is an update, the whole database is "serialized to disk".

In short, whenever a new metric value is input, it will be written to the database and the database is serialized to the disk.