695308 - Add telemetry probes for A|B testing different values for nsContentSink timing tunables

Status: NEW

(Core :: DOM: HTML Parser, defect, P5)

Description

[Henri Sivonen (:hsivonen)]

We have a bunch of tunables in http://mxr.mozilla.org/mozilla-central/source/content/base/src/nsContentSink.cpp#248 that are ancient. When trying to get the HTML5 parser in a state where it could be turned on by default, I learned that it was super-hard to change those tunables without regressing tp4.

There's a tradeoff between responsiveness and throughput there. We should probably put some telemetry probes in to measure the time nsHtml5TreeOpExecutor::RunFlushLoop() spends without returning to the event loop versus throughput with A|B testing in the wild and possibly tune the tunables in ways that achieve results we want to achieve on actual user systems regardless of how that tuning affects tp numbers.

Comment 1

[Jens Stutte [:jstutte]]

Bulk-downgrade of unassigned, >=5 years untouched DOM/Storage bugs' priority and severity.

If you have reason to believe this is wrong, please write a comment and ni :jstutte.