1414918 - hide event coalescence is slow

Status: NEW

(Core :: Disability Access APIs, defect, P2)

Description

[alexander :surkov (:asurkov)]

Current hide event coalescence approach in performance is close to what we had before EventTree and it is slow: it navigates through the whole event list for each event, which brings the event coalescence performance to o(n^2).

I'm pretty sure that this is a cause of bug 1368784, a performance regression comparing to EventTree times.

A more optimal way would be reusing EventTree logic for this part, i.e associate show events with a reorder event, and then if a new hide is contained by a reorder event, run through their associated show events and see if any show event contains that hide event.

Comment 1

[alexander :surkov (:asurkov)]

btw, 'a hide event contained by a hide event' coalescence doesn't work, this logic [1] works for 'a hide event contained by a show event' only, because hide events are unattached from the tree and you cannot traverse their parent's chain any longer.

[1] https://dxr.mozilla.org/mozilla-central/source/accessible/base/NotificationController.cpp#388