[Proposal] performance.memory API


#1

Link to github proposal

Developers currently have no mechanism to obtain the memory usage of their site.

This proposal provides an API with the following properties:

  • Consistent semantics across different OSes and browser vendors
  • No/minimal performance overhead when not used
  • Very fast to compute

This proposal relies on process-specific memory counters. It provides the most utility when the site is being hosted in a process by itself. This is an implementation detail that depends on both the browser vendor and the browsing context [e.g. # of tabs that user has open]. Despite this limitation, the API is still expected to provide utility when collected in aggregate.


#2

Would this be subject to the same “restriction” as the API for available memory? That is, rounding to the two most significant bits.


#3

This API would be very useful for engineers at Facebook. We need to understand Facebook.com’s memory usage on real end-user devices and we need to be able to evaluate the effectiveness of our fixes in a reliable way. This API would be a great help.


#4

There will be no rounding.

This seems okay from a privacy perspective since we’re limiting the API to only return non-null numbers when the website is being hosted by itself in a process.