16602 - Need to reduce directory enumeration costs via suffix-dispatch

Status: RESOLVED WONTFIX

(Core :: XPCOM, defect, P3)

Description

[Mike Shaver (:shaver emeritus)]

We should enumerate the components directory only once (_possibly_ more if we're
doing initial autoregistration, but maybe the installer should have to worry
about that), dispatching to prefs and the typelib loader and whatnot based on
file suffix.

Comment 1

[Mike Shaver (:shaver emeritus)]

The current list of places in the codebase that do enumeration of the components
directory are:
- autoregistration
  = nsNativeComponentLoader.cpp
  = mozJSComponentLoader.cpp
- default pref loading
  = nsPref.cpp
- typelib file loading
  = nsInterfaceInfoManager.cpp

Coming soon, I think:
- chrome fragment registry

Question for Simon: how do we dispatch on the Mac?  Do we require use of file
suffixes, or do I need to map from file type to ``virtual suffix''?

Question for the crowd: do we care about making autoregistration participate in
this?  It'd be a lot of work to get the ordering work, and I want
autoregistration to die anyway.  If we don't, we still reduce the number of
directory iterations by one and can probably make that iteration faster.

Comment 2

[Suresh Duddi (gone)]

Pref no longer enumerats components directory. Neeti fixed that one.

Comment 3

[Mike Shaver (:shaver emeritus)]

This appears not to matter.