Huge slowdown in state wrapper

[ghost]

Test Device

MacBook Air, Early 2015, 1.6 GHz Dual-Core Intel Core i5

Operating System

macOS 10.15.2

Browser

Safari 13.0.4

Problem Description

For phetsims/qa#488. In https://phet-dev.colorado.edu/html/energy-forms-and-changes/1.2.0-dev.12/phet-io/, I'm seeing a huge slowdown in the state wrapper on my MacBook Air. When I use the profiler query parameter, I can get the FPS down to 2 pretty quickly. The blocks like to float on their own for a few seconds. It's pretty unusable.

Visuals

[ghost]

The playback in mirror inputs can also be slow, but not nearly as slow as state.

[chrisklus]

Thanks @lmulhall-phet - the state wrapper is indeed pretty unusable when loaded with numberOfMillisecondsBetweenUpdates at its default value of 1000 ms, see #316 and the phet-io special instruction section in phetsims/qa#488.

The state slowness doesn't relate to the mirror inputs wrapper though, so if you think #328 (comment) warrants an issue of its own, please create one. Feel free to close when you see this!

[ghost]

Ah, sorry I didn't see that. Thanks, @chrisklus.