1304740 - [E10S a11y] Loading pages is 4 to 5 times slower with E10S on

Status: RESOLVED DUPLICATE of bug 1372213

(Core :: Disability Access APIs, defect)

Description

[Marco Zehe (:MarcoZ)]

STR:
1. With NVDA Next snapshot installed, and E10S a11y turned on, load https://en.wikipedia.org/wiki/World_War_I.

Result: With E10S on, this takes up to about 20 to 25 seconds, sometimes more, before NVDA starts reading the page.

2. Now turn E10S a11y off, and load the same page.

Result: It now takes between 4 and 5 seconds before NVDA starts reading the document.

Comment 1

[Marco Zehe (:MarcoZ)]

Note that other pages load slower as well, but with smaller pages the difference is not so strongly felt. But for example the news site http://www.heise.de/newsticker is also noticeably slower when loaded with E10S on.

Comment 2

[Marco Zehe (:MarcoZ)]

With the 2016-10-06 build, which contains the fix for bug 1304449, refreshing NVDA's virtual buffer takes about 12 seconds on my Surface Book with the World War I article. This used to take about 20 to 25 seconds before, so is definitely better, but not nearly as fast as with E10S off, which only takes 3 to 5 seconds. This is with the page already loaded and the buffer refreshed with NVDA+F5.

Comment 3

[Julien Cristau [:jcristau]]

Too late for firefox 52, mass-wontfix.

Comment 4

[Marco Zehe (:MarcoZ)]

Duping this to the new bug 1372213, which takes into account recent perf work by Aaron, and which are in the 2017-06-10 build onwards, and which don't even have the accessible handler enabled yet. Information in that bug now superceedes information in this one, so duping it.