Bug 1247100 - 5.08% sessionrestore (linux64) regression on push cb036027df84 (Mon Feb 8 2016)

Delta is ~114ms

Welp, let’s get some profiles.

Baseline: https://treeherder.mozilla.org/#/jobs?repo=try&revision=b2b5831cb0f7

Regression: https://treeherder.mozilla.org/#/jobs?repo=try&revision=6007945667ce

Maybe try deferring the initialization of RefreshBlocker?

Okay, here goes...

https://treeherder.mozilla.org/#/jobs?repo=try&revision=6e3bf275ac4d

Compare: https://treeherder.mozilla.org/perf.html#/compare?originalProject=fx-team&originalRevision= c882b4072883 &newProject=try&newRevision=6e3bf275ac4d&framework=1

Nope. :/

Here are the profiles:

Baseline: http://people.mozilla.org/~bgirard/cleopatra/?zippedProfile=http://mozilla-releng-blobs.s3.amazonaws.com/blobs/Try/sha512/67debc943a55a36955bd094233c86c8f6d2b998cf1e03a25ca71d2f6e7abd0ead23e96cd57fda2106bcb4b2c3d9cf30af9523f293930176510952cb97dde25e7&pathInZip=profile_sessionrestore/startup/cycle_9.sps#report=58520bc1e354c234a75fba114f2b62fde2848537&invertCallback=true&filter=%5B%7B%22type%22%3A%22RangeSampleFilter%22,%22start%22%3A1897,%22end%22%3A4259%7D%5D&selection=%22(total)%22,42

Regression: http://people.mozilla.org/~bgirard/cleopatra/?zippedProfile=http://mozilla-releng-blobs.s3.amazonaws.com/blobs/Try/sha512/01326357b4468bfa96a9e16dafd0cfff6f5863885d9fbf2fbe0703aa26c88af620fa8f1eb16c9fe0a41a38920538e5eb06b7151b78a3fd67d38dc606c4f781d5&pathInZip=profile_sessionrestore/startup/cycle_9.sps#report=b292d8eb495cd43b64d47a08f02695ce9983047a&invertCallback=true&filter=%5B%7B%22type%22%3A%22RangeSampleFilter%22,%22start%22%3A1934,%22end%22%3A4392%7D%5D&selection=%22(total)%22,935

A bunch appears to be GC...

Between firstLoad and session restore done, delta is 107

And the GC is: 80ms - still need 27...

Loading tab-content doubled, it looks like - 30ms

So that might be our regression right there.

Put into JSM:

Baseline: https://treeherder.mozilla.org/#/jobs?repo=try&revision=3b75af5d3d60

Patch: https://treeherder.mozilla.org/#/jobs?repo=try&revision=c4222aa717d5

Hey! Nice big win! Okay, that helps. Good!

Refactor a little...

Baseline: https://treeherder.mozilla.org/#/jobs?repo=mozilla-inbound&revision=d1a4b82b556a

Patch: https://treeherder.mozilla.org/#/jobs?repo=try&revision=cc61830fa5f7

Huh. Now the performance win is gone. Wtf. Maybe this win was erased?

Welp, closed.