Plugin conflict w/ Query Monitor

[lkraav]

There's a clear few second delay for QM finishing loading just by having Rocket Lazy Load active.

If you enable a large data set panel like SAVEQUERIES true, delay will be tens of seconds, if not for all intents and purposes "infinite" (depending on how high the query count is).

Hypothesis: something within post-page-load JS routines probably collide.

Symptom: visible parts of the page finish loading, then it comes time for QM to render its admin panel, but this part never finishes, and browser tab starts spinning CPU at 100%.

Cross-repo issue at johnbillion/query-monitor#350

Can you guys help figure this out? We could really use having both plugins active.

[lkraav]

I have discovered additional info, that maybe invalidates above hypothesis.

Our comments table is ballooning due to how some plugins store their metadata, and it turns out Admin Bar "Comments" menu item scans comments table on every request.

This becomes a massive performance bottleneck at hundreds of thousands of comments table rows, so I unhooked those menu items (source: https://gist.github.com/mattclements/10a997775894c7a0eba1)

I will also take a closer look at SAVEQUERIES next. It's likely this is not a JS topic at all.

[lkraav]

Update: there's definitely something still going on. Investigation continues.

[lkraav]

2.0.2: things seem better here. Will report back in about 2 more weeks, so the experience sample size becomes adequate.

[lkraav]

rocket-lazy-load-2.3.0.2
query-monitor-3.2.2

This is now confirmed to still be a problem, with plugins at their latest versions, but surprisingly only on Chrome.

All other performance issue vectors are confirmed to have been eliminated.

Firefox-64+ seems to somehow manage to avoid this issue.

PS 2.3.0.2 is missing its github tag.