17881 - [PERF] Windows event loop cleanup

Status: VERIFIED FIXED

(Core :: XUL, defect, P3)

Description

[Michael Lowe]

Attached file is a cleanup for the Windows event loop in
mozilla/widget/src/windows/nsAppShell.cpp

Please review for checkin.

Comment 1

[Michael Lowe]

Attachment: Event loop improvement

Comment 2

[troy]

For the reasons I gave in the email response.

Comment 3

[Michael Lowe]

Re-opening per my latest email comments.

Comment 4

[troy]

The reason for making the change is a potential improvement in UI
responsiveness.

If you cant get any system messages through the call to:

::PeekMessage(&msg, NULL, 0, WM_USER-1, PM_REMOVE)

then you block on:

keepGoing = ::GetMessage(&msg, NULL, 0, 0);

But, if several system and non-system messages are added to the event queue
before the call returns then you will end up processing the WM_USER
events before any system events (this is the order GetMessage returns events
from the queue) so there will be an event priority inversion. The opposite of
what you hope to achieve.

Comment 5

[Michael Lowe]

Can this be checked in now?

Comment 6

[Kevin McCluskey (gone)]

Applied patch 11/22/99 2:51PM.