[Posila] [0.16.51] On very large map Teleport/Death causes massive UPS spike

[Muppet9010]

When you are playing on a very large map and teleport long distances or die far from spawn (ie 800k tiles) there is a massive UPS spike. This can easily be enough to cause lower CPU players to be dropped when they were keeping up steadily before.
This issue doesn't occur on a new empty map when teleporting over the same distance.

An example save of a large map and associated mods folder can be found at:
save: https://www.dropbox.com/s/3rvyo9vfaykj5 ... P.zip?dl=0
mod: https://www.dropbox.com/s/rulagkteq5n60 ... r.zip?dl=0
log file: https://www.dropbox.com/s/aay0j2wzts1eh ... r.log?dl=0

Note the mods aren't needed for the issue or save to run for this test. But provided as this is the environment all players are in when they suffer the issue.

Reproduction Steps:

1. Load the save in normal game mode (with player character)
2. Teleport the player from spawn {0,0} to {800000,0} and the ups spike will occur.

   Code: Select all

   /c game.player.teleport({800000, 0})

Side Note:
if your pc has 8GB or less of Ram this save will cause memory to disk paging. This will often also occur during the UPS spike of a long teleport/death.
The map has been purged of all entities, dodads, etc between 30k and 750k except for rail etc. This is not a bug but intended to reduce save and ram size.

[posila]

Thanks for the report.
It turns out it is caused by tile renderer.
It's fixed for 0.17 now.