Sub par performance on lighthouse in Chrome v62 for `es6-unbundled` build
andrewspy opened this issue · comments
Description
Sub par performance on lighthouse in Chrome v62 out of the box in localhost setup, using polymer init
and polymer serve
.
Expected outcome
lighthouse performance should be in the 90+/100. With first pain/interactive within few sec, with a Perceptual Speed Index of less than 1,250.
Actual outcome
lighthouse performance index of only 30/100. With first paint/interactive at 13+/13+ sec respectively, with a Perceptual Speed Index of 14,000.
Live Demo
N/A
Steps to reproduce
polymer init
withpolymer-starter-kit
v3.2polymer serve
- Audit with lighthouse in Chrome v62
Browsers Affected
- Chrome
- Edge
- Firefox
- IE 11
- Safari 8
- Safari 9
Did you build the project for production? You should have this score:
Lighthouse Report
Results for: https://psk-demo-6e320.firebaseapp.com
Report: https://builder-dot-lighthouse-ci.appspot.com/report.1510755493877.html
Category Score Progressive Web App 100 Performance 93 Accessibility 100 Best Practices 94 Tested with Lighthouse version: 2.5.0
Hosted in Firebase. Preset: es5-bundled
.
@abdonrd Thanks for the reference on #1071, which I have missed the step of building for production.
I guess the major problem I am having with my build is I'm using es6-unbundled
build, which has "Critical Request Chain" of 87 (instead of 2 for es6-bundled
).
Given that I am hosting my PWA in Firebase Hosting (which support HTTP/2), should I target my build to es6-bundled
? I though es6-unbundled
can take advantages of Server Push support in HTTP/2? Does it mean there is a trade-off for having faster first paint vs granular Server Push?
The polymer-build
has an issue to improve the push-manifest.json
: https://github.com/Polymer/polymer-build/issues/260
Meanwhile, in the Polymer/shop
I see some scripts: Polymer/shop#145
@abdonrd Do you know if there is there any plan to resolve the shortfall of having es6-unbundled
build? At this stage, es6-unbundled
build simply doesn't pass the audit of lighthouse out of the box...
I have no idea. 😕
The last message I read was: https://github.com/Polymer/polymer-build/issues/260#issuecomment-342240313