An update on this,
We enabled the new Reload behavior via field trials on a couple of milestones over different channels and across platforms.
The results are simply astonishing!
High level summary of the results
HTTP response codes
The less 304s, the faster the page loads, the less data we use.
- 50% less 304s (network revalidations) on Android stable 51
- 39% less 304s on Windows beta/dev
Note: No Mac data in this summary, the impact appears to be less impressive but it's probably best to wait for stable data before making any conclusion.
Improvement to Time To first Contentful Paint
Android Beta:
- 2G median improved by 1s (other percentiles: significance not reached)
- 3G median improved by 160ms, 90%ile by 1.6s, 99%ile by 7s
- Wifi median improved by ~160ms, 90%ile by 590ms, 99%ile by 1.7s
Note: Chrome for Android stable is omitted in this summary because it didn't have Loading metrics that were constrained to Reloaded pages.
Windows Beta:- median improved by ~230ms, 90%ile by ~930ms, 99%ile by 4.4s
- Percentiles have tighter margin errors on most configurations: the performance of reloads are more consistent, contributing to a better user experience.
Health signals
We looked at the following metrics to determine if the new behavior broke user expectations:
- Volume of page loads: no significant differences (within the acceptable range of variance)
- Relative volume of Reload user actions: unchanged
- Relative volume of page load triggered by reload: no significant changes
- Relative volume of Abort via Reloads: no significant changes.
- We haven't found any report of issues in the wild.
Given these great results, we are moving forward with the change.
Best,
PS: you can try the new behavior by enabling these flags:
- Android: chrome://flags/#enable-non-validating-reload-on-refresh-content
- All platforms: chrome://flags/#enable-non-validating-reload-on-normal-reload