Bug 213520

perf/htmlcollection-backwards-iteration.html

This test recently became a flaky failure on iOS and the first failure was seen on r262935 but there are also failures on WPE starting on r262903.

History:

https://results.webkit.org/?suite=layout-tests&test=perf%2Fhtmlcollection-backwards-iteration.html

Diff:

--- /Volumes/Data/slave/ios-simulator-13-release-tests-wk2/build/layout-test-results/perf/htmlcollection-backwards-iteration-expected.txt
+++ /Volumes/Data/slave/ios-simulator-13-release-tests-wk2/build/layout-test-results/perf/htmlcollection-backwards-iteration-actual.txt
@@ -1,3 +1,50 @@
 Tests that iterating over HTMLCollection backwards is linear.
-PASS
+FAIL: got >=O(n^2) expected O(n)
 
+DEBUG LOG:
+run iteration. magnitude 2 jsObjectCountBefore 37331 jsObjectCountAfter 9039
+run iteration. magnitude 4 jsObjectCountBefore 9039 jsObjectCountAfter 9143
+run iteration. magnitude 8 jsObjectCountBefore 9143 jsObjectCountAfter 9153
+run iteration. magnitude 16 jsObjectCountBefore 9153 jsObjectCountAfter 9168
+run iteration. magnitude 32 jsObjectCountBefore 9168 jsObjectCountAfter 9191
+run iteration. magnitude 64 jsObjectCountBefore 9191 jsObjectCountAfter 9230
+run iteration. magnitude 128 jsObjectCountBefore 9230 jsObjectCountAfter 9301
+run iteration. magnitude 256 jsObjectCountBefore 9301 jsObjectCountAfter 9438
+magnitudes: 2,4,8,16,32,64,128,256
+iterations: 69079,53588,37220,16311,14890,6847,5852,1473
+numPoints 8 slope 0.00006058463555700208 intercept -0.00016136559004588597 rSquared 0.932233761110166
+numPoints 8 slope 0.002479792909714815 intercept -0.004033971660123155 rSquared 0.5744016720844201
+numPoints 8 slope 0.7415901241175854 intercept -8.677500293740575 rSquared 0.951359820277521
+rSquared 0.932233761110166 rSquaredXLog 0.5744016720844201 rSquaredXYLog 0.951359820277521
+numTriesLeft: 2
+run iteration. magnitude 2 jsObjectCountBefore 9438 jsObjectCountAfter 9238
+run iteration. magnitude 4 jsObjectCountBefore 9238 jsObjectCountAfter 9250
+run iteration. magnitude 8 jsObjectCountBefore 9250 jsObjectCountAfter 9260
+run iteration. magnitude 16 jsObjectCountBefore 9260 jsObjectCountAfter 9277
+run iteration. magnitude 32 jsObjectCountBefore 9277 jsObjectCountAfter 9298
+run iteration. magnitude 64 jsObjectCountBefore 9298 jsObjectCountAfter 9339
+run iteration. magnitude 128 jsObjectCountBefore 9339 jsObjectCountAfter 9408
+run iteration. magnitude 256 jsObjectCountBefore 9408 jsObjectCountAfter 9545
+magnitudes: 2,4,8,16,32,64,128,256
+iterations: 117792,62676,43754,27464,9919,5917,4296,1984
+numPoints 8 slope 0.000047481179453609614 intercept 0.00038038442423468655 rSquared 0.9869634138263956
+numPoints 8 slope 0.002170805572334511 intercept -0.0033637853146313815 rSquared 0.7587259752744822
+numPoints 8 slope 0.8417231267057893 intercept -9.091030394675615 rSquared 0.9888426234779988
+rSquared 0.9869634138263956 rSquaredXLog 0.7587259752744822 rSquaredXYLog 0.9888426234779988
+numTriesLeft: 1
+run iteration. magnitude 2 jsObjectCountBefore 9545 jsObjectCountAfter 9333
+run iteration. magnitude 4 jsObjectCountBefore 9333 jsObjectCountAfter 9343
+run iteration. magnitude 8 jsObjectCountBefore 9343 jsObjectCountAfter 9353
+run iteration. magnitude 16 jsObjectCountBefore 9353 jsObjectCountAfter 9372
+run iteration. magnitude 32 jsObjectCountBefore 9372 jsObjectCountAfter 9393
+run iteration. magnitude 64 jsObjectCountBefore 9393 jsObjectCountAfter 9434
+run iteration. magnitude 128 jsObjectCountBefore 9434 jsObjectCountAfter 9505
+run iteration. magnitude 256 jsObjectCountBefore 9505 jsObjectCountAfter 9642
+magnitudes: 2,4,8,16,32,64,128,256
+iterations: 90901,55535,37932,17428,9978,6219,3092,2546
+numPoints 8 slope 0.000039724539509521464 intercept 0.0008736725458908445 rSquared 0.9192615399826782
+numPoints 8 slope 0.0019946943488229735 intercept -0.002815663498221913 rSquared 0.8524307390097007
+numPoints 8 slope 0.7806004217721016 intercept -8.775197754409973 rSquared 0.9917623952783599
+rSquared 0.9192615399826782 rSquaredXLog 0.8524307390097007 rSquaredXYLog 0.9917623952783599
+
+