Opening large Perfetto traces without native acceleration

[Lalit Maganti]

If you're not interested in opening large traces with Perfetto, you can stop reading now

Hi all,

The Perfetto UI has long been limited to only using 4GB of memory to open and process traces. In practice, this meant we could open around 1-2GB trace sizes directly in the UI with anything more requiring use of the "native accelerator" (i.e. running a binary on your machine which the UI could communicate with).

This 4GB limitation came directly from WASM implementations in the browser. However, earlier this year, Firefox and Chrome added support for Memory64, a mechanism to support up to 16GB of memory in a WASM-tab. Perfetto added support for memory64 earlier this week.

To this end:

• The Perfetto UI now supports opening 4-8GB traces natively without needing the native accelerator on Autopush channel
• This change will roll to Canary and Stable channels of the UI in coming weeks.
• The native accelerator will continue to be fully supported but it is no longer strictly necessary

We hope you will enjoy this new feature!

Best,

Lalit (on behalf of the Perfetto team)