There are two cases to consider with this test: 1) The tab has been opened from the parent 2) The tab has been opened from content via a target="_blank" link, for example This was spun out of the work done in bug 1251732, as we suspect there's a slow path here for e10s that we're not currently measuring.

This is necessary in order to be able to open new tabs from the initial browser window, since the initial browser window needs to have its BrowserDOMWindow attribute set when it goes remote - and if it fires before the onLoad handler in browser.js, the BrowserDOMWindow attribute that's set on the XUL window (which gets copied over to the remote browser), hasn't been set yet. Review commit: https://reviewboard.mozilla.org/r/38013/diff/#index_header See other reviews: https://reviewboard.mozilla.org/r/38013/

tabpaint measures how long it takes to open a new tab and show its content. This is a mostly done work-in-progress and isn't yet ready for review. Review commit: https://reviewboard.mozilla.org/r/38015/diff/#index_header See other reviews: https://reviewboard.mozilla.org/r/38015/

Comment on attachment 8726458 [details] MozReview Request: Bug 1253382 - Add a new tabpaint talos test. r?jmaher Review request updated; see interdiff: https://reviewboard.mozilla.org/r/38015/diff/1-2/

Comment on attachment 8726458 [details] MozReview Request: Bug 1253382 - Add a new tabpaint talos test. r?jmaher https://reviewboard.mozilla.org/r/38015/#review34679 keep in mind that we need to sign addons now, so any new addons or changes to existing ones need a signed addon. If you update the source, you can see it done for all other addons. If you look in test.py you will see references to the .xpi instead of the source. Some tips for signing addons: https://wiki.mozilla.org/EngineeringProductivity/HowTo/SignExtensions ::: testing/talos/talos/test.py:254 (Diff revision 2) > + 'browser.link.open_newwindow.restriction': 2, can you provide a brief comment about what these values of 3 and 2 mean?

Review commit: https://reviewboard.mozilla.org/r/38241/diff/#index_header See other reviews: https://reviewboard.mozilla.org/r/38241/

Comment on attachment 8726457 [details] MozReview Request: Bug 1253382 - Force the initial browser remoteness only after the browser's onLoad has fired. r?jmaher Review request updated; see interdiff: https://reviewboard.mozilla.org/r/38013/diff/1-2/

Comment on attachment 8726458 [details] MozReview Request: Bug 1253382 - Add a new tabpaint talos test. r?jmaher Review request updated; see interdiff: https://reviewboard.mozilla.org/r/38015/diff/2-3/

Comment on attachment 8726457 [details] MozReview Request: Bug 1253382 - Force the initial browser remoteness only after the browser's onLoad has fired. r?jmaher https://reviewboard.mozilla.org/r/38013/#review34755 thanks, this looks nice and simple.

Comment on attachment 8726802 [details] MozReview Request: Bug 1253382 - Sign the most recent version of TalosPowers. r?jmaher https://reviewboard.mozilla.org/r/38241/#review34759 ship it real good

Comment on attachment 8726458 [details] MozReview Request: Bug 1253382 - Add a new tabpaint talos test. r?jmaher https://reviewboard.mozilla.org/r/38015/#review34761 thanks for the signed addon, talos.json changes and the comments in test.py. Please add an entry here: https://wiki.mozilla.org/Buildbot/Talos/Tests

https://hg.mozilla.org/integration/mozilla-inbound/rev/23589403e775 https://hg.mozilla.org/integration/mozilla-inbound/rev/64db01968f1d https://hg.mozilla.org/integration/mozilla-inbound/rev/1b921419d549

https://hg.mozilla.org/mozilla-central/rev/23589403e775 https://hg.mozilla.org/mozilla-central/rev/64db01968f1d https://hg.mozilla.org/mozilla-central/rev/1b921419d549

This set of changes seems to have changed the results for tp5o responsiveness, I'm assuming that's expected: https://treeherder.allizom.org/perf.html#/alerts?id=445 https://treeherder.allizom.org/perf.html#/graphs?series=%5Bmozilla-inbound,e359bef1059e570e650d54089ec3159e483d16b6,1%5D&series=%5Bmozilla-central,e359bef1059e570e650d54089ec3159e483d16b6,0%5D&series=%5Bfx-team,e359bef1059e570e650d54089ec3159e483d16b6,0%5D

this is for winxp e10s (regular and pgo). I don't think it is expected, most likely the cause of the pageloader addon change: https://hg.mozilla.org/integration/mozilla-inbound/rev/64db01968f1d