When comments are refreshed, each `Comment` gets rendered 4-5 times due to reference invalidation for `othersReacts` (the data didn't actually change).
For selectors without transformation, there is no need to memoize using `createSelector` -- just access it directly. Also, don't do things like `return a[id] || {}` in a reducer, because the reference to the empty object will be different on each call.
Always return directly from the state so that the same reference is returned.
This simple change avoided the wasted resources needed for `createSelector`, and reduced to render to just 2 (initial render, and when reactions are fetched).
followedTags:
- Moved the filtering to the reducer side, so that we don't do it every time. We can't rely on `createSelector` because the store will be invalidated on each `USER_STATE_POPULATE`, unfortunately.
tags:
- Memoize via re-reselect for the "ForUri" selector.
`makeSelectDataForUri` always returns a new reference, so `ClaimPreview` was constantly being rendered. It's pretty expensive since `ClaimPreview`'s rendering checks against a huge blocklist, which is another issue on it's own.
- This commit tests the usage of `re-reselect` as the solution to the multi-instance memoization problem (https://github.com/toomuchdesign/re-reselect/blob/master/examples/1-join-selectors.md)
## Ticket
"Overall React Lag or Extra Re-renders / Volume slider laggy since v0.48"
## The problem
Every redux update results in each mounted component's prop mapping function (the `select` and `perform` stuff) to be recalculated. This is normal per redux, but we do lots of heavy stuff there.
The slider was sending tons of redux update for the Volume and Muted setting.
## Changes
The redux volume/muted setting is just used to restore vjs to the user's setting on the next video, so it doesn't need to be updated immediately/constantly -- vjs keeps it's own video settings. Debounced that action.
- 251 Dragging the floating player is super laggy
Recent changes and/or refactoring combined the effects or added dependancies into the effects, causing them to re-run excessively.
- Restored effects to their original behavior.
- Don't perform the position check when dragging -- only do it when released.
- Do proper debouncing for the 'resize' listener -- the previous method was incorrect as a new function is created on each render.
## Issue
60 setting.Get calls spiked since October
It was called 24 times per livestream page load.
## Notes
The effect was intended to be a one-time effect, but the dependency was changed in 2f4dedfb
