Noticed during routine review of Grafana: startup-manifest-size, on 5 May (2021-05-05) there was a sudden increase of 2.1 KB on all page views for all users, due to the startup registry cost added by the deployment of GrowthExperiments, which currently registers 35 distinct module bundles.
|Startup payload size (last 6 months)|
At 2.1KB for a single extension, that places it right up with ContentTranslation and VisualEditor, which have upcoming mitigations of their own that are difficult for legacy reasons, but this does not apply to new extensions which should generally not need more than three (3) modules. I regretfully did not notice this during our team's perf review in Nov 2020 (ref T240201). At the time there were 25 modules bundldes, but this has since then increased to 35. That suggests module bundles are used for something other than logical entry points or performance optimisations, but for code organisation, which is not what bundles are for.
From a quick look at the codebase, it seems like these should be easy to consolidate. If this is not easy to do for some reason, I think we need to work together on a viable solution and to block deployment until that is done.