[MCM-949] Performance in 1.15 is horrendous in redstone/behavior intense maps.

Partner Rank: 1

Partner Team Reporting: Jigarbov Productions

Verification builds and Platforms: 1.15.0.51 3706814 UAP Win10

Summary:

Performance in 1.15 is horrendous in redstone/behavior intense maps. Specifically in maps like Mutant Battle Arena we go from 60fps, frame time 16.6 in 1.14 to frame time 30+and the fps is sub 40 and that's on a good pc.

Impact:

Performance of redstone and behaviors is tanking in the client making many clients crash and other pieces of content unplayable. Mutant Battle Arena is my most popular piece and it performing so bad is bad news. Impact will be worse on consoles.

Repro Steps:

Download Mutant Battle Arena from the store
Enable Battle Arena Mode
Teleport to Llano options
Summon one of each mob
Go to boss panel
summon one of each (if currently locked just put a button on top)
go to ecru panel
summon one of each mob
go to emperor chair and open gates

Observed Results:

Frame time goes over 30 and fps goes to sub 40 on a decent pc. Would very likely be significantly worse on console and mobile.

Expected Results:
in 1.14 and earlier, frame time is demonstrably better, 16, fps is hitting 60 almost all the time even with a screen full of mobs.

Screenshots/Videos attached:

See video for full repro steps and example of the performance drop. https://www.youtube.com/watch?v=MpC6LW3cHpA