About 4% of the time before the first browser window is shown is spent in http://searchfox.org/mozilla-central/source/services/sync/Weave.js and almost all of the time spent there is importing resource://services-sync/util.js I think this should be a lazy getter. Here it is on a Mac startup profile: https://perfht.ml/2pNYWEq Equivalent Windows profile: https://perfht.ml/2pO7v1W

Actually, Promise.jsm is visible in the profile too, so it would be nice to stop using it there and use a native promise instead. FileUtils.jsm should also become a lazy getter... or maybe even better import it right before its only use in the file.

There's a good chance that bug 1353571 will fix this.

(In reply to Mark Hammond [:markh] from comment #2) > There's a good chance that bug 1353571 will fix this. Ok, the current patches there don't seem to touch the Weave.js file, but as long as it gets fixed, I don't really care in which bug we do it :-).

Wish I could have done more and remove completely that Svc abomination, but it's a bit more work.

Comment on attachment 8863924 [details] Bug 1358648 part 1 - Clean-up some Weave imports. https://reviewboard.mozilla.org/r/135652/#review138674 ::: services/common/utils.js:14 (Diff revision 1) > Cu.import("resource://gre/modules/XPCOMUtils.jsm"); > -Cu.import("resource://gre/modules/osfile.jsm") > Cu.import("resource://gre/modules/Log.jsm"); > +XPCOMUtils.defineLazyModuleGetter(this, "OS", > + "resource://gre/modules/osfile.jsm"); > +XPCOMUtils.defineLazyModuleGetter(this, "Promise", I believe we can just kill use of Promise.jsm and DOM promises should just magically work.

Comment on attachment 8863925 [details] Bug 1358648 part 2 - Remove util.js Svc.{DefaultPrefs,Session,Idle, FormHistory} and Str. https://reviewboard.mozilla.org/r/135654/#review138680

Comment on attachment 8863926 [details] Bug 1358648 part 3 - Remove Async, Services and XPCOMUtils from util.js. https://reviewboard.mozilla.org/r/135656/#review138690

Pushed by eoger@mozilla.com: https://hg.mozilla.org/integration/autoland/rev/8d0b6d84a8e9 part 1 - Clean-up some Weave imports. r=markh https://hg.mozilla.org/integration/autoland/rev/dff6d3f923d7 part 2 - Remove util.js Svc.{DefaultPrefs,Session,Idle, FormHistory} and Str. r=markh https://hg.mozilla.org/integration/autoland/rev/9e6ae4133c2e part 3 - Remove Async, Services and XPCOMUtils from util.js. r=markh

https://hg.mozilla.org/mozilla-central/rev/8d0b6d84a8e9 https://hg.mozilla.org/mozilla-central/rev/dff6d3f923d7 https://hg.mozilla.org/mozilla-central/rev/9e6ae4133c2e