When we had it in the loop, we would continually reduce it, which held the
possibility of bumping it down an epoch due to double imprecision. Now
we only reduce it once, using all rAF callbacks get the same timestamp.
Differential Revision: https://phabricator.services.mozilla.com/D44526
In Bug 1387894 we created a mode for Firefox where it unconditionally clamps all timestamps to 20 microseconds. This happens if you disable privacy.reduceTimerPrecision (which is on by default) and is so we don't inadvertently leak super-high-resolution (nanosec) timestamps.
As part of that patch, we started clamping animation timestamps - which are exempted from privacy.reduceTimerPrecision because it was too difficult to get them working at the time. (We should still fix that though.)
This caused new test failures, and one of those was a comparison between document timelines and the timestamp in requestAnimationFrame. we were not clamping the timestamp in requestAnimationFrame under the logic that it fires in predictable intervals.
However discussions about the WPT change we made to 'fix' the now-broken comparison https://github.com/web-platform-tests/wpt/pull/18172 and https://github.com/web-platform-tests/wpt/pull/18357 showed me that document.timeline is supposed to be slaved to the requestAnimationFrame timestamp (or vice versa.)
The correct fix is therefore to unconditionally clamp the requestAnimationFrame timestamp AND the document.timeline timestamp. In doing so we also start clamping/jittering the requestAnimationFrame timestamp in Resist Fingerprinting mode, so that might cause some new/unexpected behaviors for that mode we should watch out for.
Differential Revision: https://phabricator.services.mozilla.com/D43788
Rather than short circuit the refresh driver, this instead only bypasses painting on
Android when WebVR is in immersive mode.
Differential Revision: https://phabricator.services.mozilla.com/D42973
Collect telemetry for the number of pending style and layout flush requests per
flush and the number of style and layout flushes per nsRefreshDriver::Tick. A
style flush reports only style requests, but a layout flush reports style and
layout requests since flushing layout implies a style flush also.
Differential Revision: https://phabricator.services.mozilla.com/D40756
Converts layout.idle_period.required_quiescent_frames and layout.idle_period.time_limit to static prefs. These are the last prefs in nsLayoutUtils::initialize(), but since the function still calls nsComputedDOMStyle::RegisterPrefChangeCallbacks() the commit retains it.
Differential Revision: https://phabricator.services.mozilla.com/D41856
This requires replacing inclusions of it with inclusions of more specific prefs
files.
The exception is that StaticPrefsAll.h, which is equivalent to StaticPrefs.h,
and is used in `Codegen.py` because doing something smarter is tricky and
suitable for a follow-up. As a result, any change to StaticPrefList.yaml will
still trigger recompilation of all the generated DOM bindings files, but that's
still a big improvement over trigger recompilation of every file that uses
static prefs.
Most of the changes in this commit are very boring. The only changes that are
not boring are modules/libpref/*, Codegen.py, and ServoBindings.toml.
Differential Revision: https://phabricator.services.mozilla.com/D39138
For a slow tick, where the processing time takes longer than 1/60th sec, record
telemetry for the percentage of that time spent in each sub-system processing
Events, Style), Reflow, Display and Paint.
Differential Revision: https://phabricator.services.mozilla.com/D38962
gfxPrefs Live preferences are almost identical to StaticPrefs.
We leave aside for now those that set a custom change callback as this feature isn't yet supported in StaticPrefs.
Differential Revision: https://phabricator.services.mozilla.com/D31256
gfxPrefs Live preferences are almost identical to StaticPrefs.
We leave aside for now those that set a custom change callback as this feature isn't yet supported in StaticPrefs.
Differential Revision: https://phabricator.services.mozilla.com/D31256
gfxPrefs Live preferences are almost identical to StaticPrefs.
We leave aside for now those that set a custom change callback as this feature isn't yet supported in StaticPrefs.
Differential Revision: https://phabricator.services.mozilla.com/D31256
According to the procedure to update animations and send events[1] the UA should
update all timelines first and _then_ run a microtask checkpoint.
As a result, when we run callbacks for the finished promise on an Animation they
should see the fully up-to-date state of all animations, regardless of which
timeline they are attached to.
However, that is currently not the case since we run a microtask checkpoint
after updating each individual timeline.
This difference will become more significant later in this patch series when we
introduce another step--removing replaced animations--that _also_ should happen
before we run the microtask checkpoint (so that the promise callbacks always see
a fully-up-to-date state).
This patch makes our handling a little more in line with the spec. It's not
quite the same because it's possible there may be other refresh driver observers
that trigger a microtask checkpoint in between ticking the different timelines
but that case is expected to be rare and fixing it would require maintaining
a separate queue for timeline observers that we run after all other observers--
so it is probably not necessary to fix that case at this stage.
The test added in this patch fails without the code changes in this patch.
[1] https://drafts.csswg.org/web-animations-1/#update-animations-and-send-events
Differential Revision: https://phabricator.services.mozilla.com/D30319
nsRefreshDrivers belonging to fully-loaded documents in content processes
now correctly stop their timer when no observers are present.
Differential Revision: https://phabricator.services.mozilla.com/D28339
This patch changes remaining things under `layout/`. However, there are some
places which still need to use `nsIPresShell`. That will be fixed in a
follow up bug.
Differential Revision: https://phabricator.services.mozilla.com/D27477
In the next patch in this series we want to compare the handle of frame
callbacks we are about to run, with a set of canceled handles stored on the
document. This patch makes us pass the handles along with the callbacks so we
can do that.
Incidentally doing this allows us to just swap array elements when building up
the refresh driver's set of callbacks to run. That is hopefully a little more
efficient than running the implicit conversion operator on each item and then
appending to an array.
Differential Revision: https://phabricator.services.mozilla.com/D20973
`nsPresContext` should use `mozilla::PresShell` directly instead of
`nsIPresShell`. This patch makes it.
Unfortunately, `nsPresContext` and `nsIFrame` have `PresShell()`. Therefore,
we cannot use `PresShell*` in its methods so that this patch uses `mozilla::`
namespace prefix.
It might be better to rename them as `PresShellPtr()` in another bug.
Differential Revision: https://phabricator.services.mozilla.com/D25721
fcp is often almost blank paint, but the next couple paints have more content.
But in order to not regress page load time, reduce frame rate later during the page load.
Differential Revision: https://phabricator.services.mozilla.com/D24636
The Timestamp implementation on Windows seems to be based off of two system APIs: GetTickCount64 and QueryPerformanceCounter. QPC seems to be preferred over GTC, unless a "failure" in QPC is detected.
There is code in the Timestamp implementation to detect if QPC "fails" be comparing elapsed time of QPC to elapsed time of GTC.
Through logging on try server I observed the following in different failures:
1) the QPC failure detection kicks in a lot and disables use of QPC
2) the QPC of the vsync timestamp was in the future compared to the QPC of TimeStamp::Now().
3) the QPC of TimeStamp::Now() was missing (presumably because it was disabled) and the GTC of the vsync timestamp was in the future compared to the GTC of TimeStamp::Now()
4) the vsync timestamp printf of raw GTC and QPC values matched at the source (SoftwareDisplay::NotifyVsync) and in the refresh driver, so the vsync timestamp wasn't getting messed up.
I guess we could spend more time on the error detection in our Windows TimeStamp code, but this failure is only happening on 32-bit machines.
Here's a patch to disable the assertions on 32-bit Windows. Depends how important we think this assertion is relative to the work to investigate more.
Differential Revision: https://phabricator.services.mozilla.com/D22453
In the next patch in this series we want to compare the handle of frame
callbacks we are about to run, with a set of canceled handles stored on the
document. This patch makes us pass the handles along with the callbacks so we
can do that.
Incidentally doing this allows us to just swap array elements when building up
the refresh driver's set of callbacks to run. That is hopefully a little more
efficient than running the implicit conversion operator on each item and then
appending to an array.
Differential Revision: https://phabricator.services.mozilla.com/D20973