205895 - nsIMIMEInfo.getFileExtensions should use nsIStringEnumerator

Status: RESOLVED FIXED

(Core :: Networking, defect, P2)

Description

[Alec Flett]

USing spacetrace I noticed that on startup on windows,
nsExternalHelperAppService scans the list of every file extension in every mime
type. I think its reading in mime types from the system. This accounted for some
300 seperate 24 byte allocations from calling nsIMIMEInfo::GetFileExtensions
(well, 3 to 4 bytes really, but with alignment and malloc overhead, they're at
least 24 bytes)

I switched to using nsIUTF8StringEnumerator, and I managed to eliminate all of
those allocations, save the 8-12 bytes for the enumerator itself.

patch forthcoming.

Comment 1

[Alec Flett]

Attachment: switch to string enumerator

and here's the patch, looking for reviews.

Comment 2

[Alec Flett]

Comment on attachment 123480 [details] [diff] [review]
switch to string enumerator

no huge rush on these, but the patch is pretty straight forward.

Comment 3

[Darin Fisher]

Comment on attachment 123480 [details] [diff] [review]
switch to string enumerator

i like it!  sr=darin

Comment 4

[Boris Zbarsky [:bzbarsky]]

Comment on attachment 123480 [details] [diff] [review]
switch to string enumerator

r=me if you put back the |var extString = "";| that you removed in the last
hunk in that diff -- that's still needed...

Looks nice.  ;)

Comment 5

[Alec Flett]

fix is in!