1264097 - We checkerboard a lot on the streams spec

Status: RESOLVED DUPLICATE of bug 1256677

(Core :: Panning and Zooming, defect)

Description

[(no longer active)]

https://streams.spec.whatwg.org/

We pretty much checkerboard constantly when scrolling the streams spec.

Comment 1

[Botond Ballo [:botond]]

As in bug 1264035, an about:checkeboard report would be helpful.

Comment 2

[(no longer active)]

(In reply to Botond Ballo [:botond] from comment #1)
> As in bug 1264035, an about:checkeboard report would be helpful.

It's next to impossible for me to tell how one is supposed to use this tool.  :-)

What I did was scroll around a bit, then open about:checkerborad, select the top most item under "Most recent checkerboarding reports" (with severity 37) and paste it below.  I'm also including a few of the items following it.  Hopefully this is useful.

 -- checkerboarding starts below --
RENDERTRACE 0.008021 rect red 0 20399 1381 967 // viewport
RENDERTRACE 0.019783 rect red 0 20399 1381 967 // viewport
RENDERTRACE 9.38494 rect yellow -345.25 21570.4 2071.5 3384.5 // requested displayport velocity (0,72.125)
RENDERTRACE 29.701 rect yellow -345.25 21962.5 2071.5 3384.5 // requested displayport velocity (0,65.5294)
RENDERTRACE 42.3935 rect yellow -345.25 22510.5 2071.5 3384.5 // requested displayport velocity (0,66.25)
RENDERTRACE 52.6197 rect brown 0 0 1381 79352.1 // page
RENDERTRACE 52.628 rect lightgreen 0 19840 1381 3584 // painted displayport painttime 126.549
Checkerboarded for 1 frames (52.7161 ms), 339726 peak, 37 severity.

RENDERTRACE 1791.48 rect brown 0 0 1381 79352.1 // page
RENDERTRACE 1791.48 rect lightgreen 0 11648 1381 3584 // painted displayport painttime 13.6792
RENDERTRACE 1811.45 rect brown 0 0 1381 79352.1 // page
RENDERTRACE 1811.45 rect lightgreen 0 11776 1381 3584 // painted displayport painttime 18.6779
RENDERTRACE 1835.13 rect brown 0 0 1381 79352.1 // page
RENDERTRACE 1835.13 rect lightgreen 0 11648 1381 3584 // painted displayport painttime 22.9687
RENDERTRACE 1877.82 rect brown 0 0 1381 79352.1 // page
RENDERTRACE 1877.82 rect lightgreen 0 11776 1381 3584 // painted displayport painttime 17.5543
RENDERTRACE 1884.46 rect yellow -345.25 14642 2071.5 3384.5 // requested displayport velocity (0,91.1111)
RENDERTRACE 1899.7 rect red 0 13573 1381 967 // viewport
RENDERTRACE 1910.57 rect yellow -345.25 13168.2 2071.5 3384.5 // requested displayport velocity (0,32.1587)
RENDERTRACE 1910.76 rect yellow -345.25 14036.2 2071.5 3384.5 // requested displayport velocity (0,32.1587)
RENDERTRACE 1918.1 rect brown 0 0 1381 79352.1 // page
RENDERTRACE 1918.11 rect lightgreen 0 13056 1381 3584 // painted displayport painttime 39.0661
RENDERTRACE 1918.28 rect red 0 14441 1381 967 // viewport
RENDERTRACE 1918.28 rect red 0 14441 1381 967 // viewport
RENDERTRACE 1927.7 rect yellow -345.25 16921.2 2071.5 3384.5 // requested displayport velocity (0,110.118)
RENDERTRACE 1933.84 rect red 0 15377 1381 967 // viewport
RENDERTRACE 1933.84 rect red 0 15377 1381 967 // viewport
RENDERTRACE 1943.62 rect yellow -345.25 17605 2071.5 3384.5 // requested displayport velocity (0,102.588)
 -- checkerboarding starts below --
RENDERTRACE 1950.43 rect red 0 16249 1381 967 // viewport
RENDERTRACE 1950.43 rect red 0 16249 1381 967 // viewport
RENDERTRACE 1960.7 rect yellow -345.25 18232.6 2071.5 3384.5 // requested displayport velocity (0,95.2941)
RENDERTRACE 1976.6 rect yellow -345.25 18944 2071.5 3384.5 // requested displayport velocity (0,93.75)
RENDERTRACE 1983.03 rect brown 0 0 1381 79352.1 // page
RENDERTRACE 1983.03 rect lightgreen 0 14592 1381 3584 // painted displayport painttime 98.5765
RENDERTRACE 1984.91 rect red 0 17809 1381 967 // viewport
RENDERTRACE 1984.92 rect red 0 17809 1381 967 // viewport
RENDERTRACE 1994.27 rect yellow -345.25 19500.1 2071.5 3384.5 // requested displayport velocity (0,87.875)
RENDERTRACE 2000.51 rect red 0 18512 1381 967 // viewport
RENDERTRACE 2000.52 rect red 0 18512 1381 967 // viewport
RENDERTRACE 2010.46 rect yellow -345.25 19904.4 2071.5 3384.5 // requested displayport velocity (0,77.6471)
RENDERTRACE 2026.97 rect yellow -345.25 20426.5 2071.5 3384.5 // requested displayport velocity (0,73.5294)
RENDERTRACE 2037.76 rect brown 0 0 1381 79352.1 // page
RENDERTRACE 2037.77 rect lightgreen 0 17536 1381 3584 // painted displayport painttime 127.02
Checkerboarded for 3 frames (87.5047 ms), 1335427 peak, 7912 severity.

RENDERTRACE 1000.36 rect red 0 78331.1 1381 967 // viewport
RENDERTRACE 1016.72 rect red 0 78144.1 1381 967 // viewport
RENDERTRACE 1028.56 rect yellow -345.25 74294 2071.5 3384.5 // requested displayport velocity (0,-84.5714)
RENDERTRACE 1033.8 rect red 0 77617.1 1381 967 // viewport
RENDERTRACE 1054.91 rect yellow -345.25 75471.6 2071.5 3384.5 // requested displayport velocity (0,-37.4698)
RENDERTRACE 1055.03 rect yellow -345.25 74865.6 2071.5 3384.5 // requested displayport velocity (0,-37.4698)
RENDERTRACE 1070.47 rect yellow -345.25 73319.3 2071.5 3384.5 // requested displayport velocity (0,-76.4)
RENDERTRACE 1072.37 rect brown 0 0 1381 79352.1 // page
RENDERTRACE 1072.37 rect lightgreen 0 74240 1381 3584 // painted displayport painttime 43.8199
RENDERTRACE 1074.93 rect brown 0 0 1381 79352.1 // page
RENDERTRACE 1074.93 rect lightgreen 0 74752 1381 3584 // painted displayport (this layertree updated)
RENDERTRACE 1074.99 rect red 0 76438.1 1381 967 // viewport
RENDERTRACE 1083.68 rect red 0 76438.1 1381 967 // viewport
RENDERTRACE 1088.13 rect yellow -345.25 73261.1 2071.5 3384.5 // requested displayport velocity (0,-57.8889)
RENDERTRACE 1102.14 rect brown 0 0 1381 79352.1 // page
RENDERTRACE 1102.14 rect lightgreen 0 73216 1381 3584 // painted displayport painttime 31.6703
 -- checkerboarding starts below --
RENDERTRACE 1102.22 rect red 0 75917.1 1381 967 // viewport
RENDERTRACE 1105.1 rect brown 0 0 1381 79352.1 // page
RENDERTRACE 1105.1 rect lightgreen 0 73216 1381 3584 // painted displayport painttime 16.9745
RENDERTRACE 1105.2 rect yellow -345.25 72824.4 2071.5 3384.5 // requested displayport velocity (0,-56.2353)
Checkerboarded for 1 frames (14.9051 ms), 116004 peak, 1465 severity.

 -- checkerboarding starts below --
RENDERTRACE 0.009 rect red 0 73737 1381 967 // viewport
RENDERTRACE 1.42447 rect red 0 73737 1381 967 // viewport
RENDERTRACE 19.6632 rect yellow -345.25 75196.2 2071.5 3384.5 // requested displayport velocity (0,106.717)
RENDERTRACE 19.7918 rect yellow -345.25 77196.2 2071.5 3384.5 // requested displayport velocity (0,106.717)
RENDERTRACE 36.0639 rect yellow -345.25 82633.9 2071.5 3384.5 // requested displayport velocity (0,245.625)
RENDERTRACE 40.3163 rect brown 0 0 1381 79352.1 // page
RENDERTRACE 40.3229 rect lightgreen 0 73472 1381 3584 // painted displayport painttime 72.775
RENDERTRACE 40.5483 rect red 0 77702 1381 967 // viewport
RENDERTRACE 52.831 rect yellow -345.25 77176.3 2071.5 3384.5 // requested displayport velocity (0,0)
RENDERTRACE 60.3123 rect brown 0 0 1381 79352.1 // page
RENDERTRACE 60.3156 rect lightgreen 0 75768.1 1381 3584 // painted displayport painttime 64.1103
RENDERTRACE 60.6038 rect brown 0 0 1381 79352.1 // page
RENDERTRACE 60.606 rect lightgreen 0 75768.1 1381 3584 // painted displayport painttime 24.5539
Checkerboarded for 3 frames (60.7063 ms), 1335427 peak, 7358 severity.

 -- checkerboarding starts below --
RENDERTRACE 0.008458 rect red 0 70443 1381 967 // viewport
RENDERTRACE 6.33385 rect yellow -345.25 69527.4 2071.5 3384.5 // requested displayport velocity (0,10.2857)
RENDERTRACE 11.8852 rect red 0 70479 1381 967 // viewport
RENDERTRACE 12.4029 rect yellow -345.25 69696.4 2071.5 3384.5 // requested displayport velocity (0,14.4444)
RENDERTRACE 21.3954 rect yellow -345.25 70053 2071.5 3384.5 // requested displayport velocity (0,24.75)
RENDERTRACE 28.278 rect yellow -345.25 70843 2071.5 3384.5 // requested displayport velocity (0,49.4286)
RENDERTRACE 36.1572 rect yellow -345.25 72297 2071.5 3384.5 // requested displayport velocity (0,92.75)
RENDERTRACE 44.3065 rect yellow -345.25 73516.2 2071.5 3384.5 // requested displayport velocity (0,122)
RENDERTRACE 44.4152 rect brown 0 0 1381 79352.1 // page
RENDERTRACE 44.4183 rect lightgreen 0 69120 1381 3584 // painted displayport painttime 71.0167
Checkerboarded for 2 frames (44.5392 ms), 294153 peak, 1704 severity.

Comment 3

[Kartikaya Gupta (email:[e-mail])]

Thanks! Most of these appear to be because of slow painting. There's one (the third one) where the paints generally seemed pretty fast but I think the velocity bias was throwing off the displayport. I've filed bug 1265880 to experiment with tuning the velocity bias, and will dupe this to our checkerboarding metabug (see bug 1256677 comment 0 for our new process on handling checkerboarding issues).

Comment 4

[Markus Stange [:mstange]]

Bug 1169502 will help with this. And so would setting a z-index on the fixed element that is above the <h4> elements' z-index.