962026 - [Meta] OS.File is too slow to start

Status: RESOLVED WONTFIX

(Toolkit Graveyard :: OS.File, defect)

Description

[David Teller [:Yoric] - still alive but not very active]

Experience indicates that OS.File is not suitable for critical startup path as loading the OS.File ChromeWorker can take 700 ms on a fast machine – before even the JS code starts being executed (Telemetry pending bug 916076).

We need to fix the issue.

Comment 1

[David Teller [:Yoric] - still alive but not very active]

I believe that the best solution is to provide a native implementation of OS.File for use in the main thread. We can perform the implementation function by function until we have everything that is needed for a fast startup.

Comment 2

[Zibi Braniecki [:zbraniecki][:gandalf]]

In bug 1280671 I'm trying to move away from using XHR+chrome:// for loading l10n resources.

Unfortunately, my initial experience with OS.File.read is matching this bug - it's around 5 times slower.

I set up an experiment to load 5 l10n resource files on my non-omni.ja'ed browser (so, the files are physically in directories on the hard drive).

Then I loaded them once using following strategies:

1) XHR+chrome:// - 12ms
2) XHR+file:// - 15ms
3) NetUtil+file:// - 16ms
4) OS.File.read + /path/to/the/file - 50ms

So, this bug indicates that loading OS.File is slow. But also using OS.File.read is slow :(