New year, new performance struggles. The 1.6 update for RimWorld already improved performance quite a bit - especially for late-game colonies, when it matters the most. There are still enough bottlenecks though and the use of mods can still put a huge strain on the game's performance. This is specifically true with the rise of questionable 'vibe-coded' mods on the Workshop these days, ignoring best practice coding methods to be as performant as possible.
So here's a friendly reminder to finally stop using your redundant, pre-1.2 mods that are known to be significantly hard on performance - but since you people never listen to that, here's a list of mods aiming to improve RimWorld's performance instead. They tend to improve different things and are typically meant to be used together if needed and unless stated differently in their descriptions. We also only highlight mods that are at least somewhat tried-and-tested and basically approved by the Dubs Performance Discord, which harbours most of the knowledge and skill in regards to game performance.
So, before blindly subbing to performance mods; consider checking in there first, using JuMLi to scan your modlist for known problematic mods and check your actual bottlenecks with Performance Analyzer (link below) - then pick from this list whatever you think will improve your experience. The general rule still is to only use mods if they are necessary, since they can always cause issues. Basically all of them can be added/removed without issues to/from an ongoing save as well. At the same time though; most of them are meant to work together without issues.
In the future - if time allows for - we might be adding some general rating to each mod on how much performance-improvement one can expect. Predictions like that are usually rather vague and situational though, so the rating will be a rough estimate at best.
Long-time staple for performance. Contains a variety of improvements to vanilla methods, adds caching and throttling to some and allows to disable different UI elements and sound via the mod-settings.
Applies the Variable Tick Rate (VTR) feature - introduced in 1.6 - to more aspects than the basegame covers. Allowing for ticking things to be checked less frequently. VTR still seems to negatively affect some jobs - even in vanilla RimWorld - but at this point, the mod should work without problems, even if the multiplier is set higher than 6x - the few remaining things that work in unintended ways when off-screen are reported to Ludeon and will hopefully be fixed in time.
A relatively new mod from the author of Slower Pawn Tick Rate, covering some random aspects of the game not covered in their other mod. Makes improvements to mothballing, meditation (especially relevant when used with VPE) and other things. Might still need some testing, but the changes seem rather unobtrusive and there are no known issues reported at the time writing.Â
Initially started as a joke-mod to make fun of vibe-coded mods, Placebo now has been transformed to an actually working performance mod, mostly changing mothballing to be more aggressive with how worldPawns apply to be mothballed. It does so in a similar manner like Performance Fish previously with an opt-in feature.
If you prefer a less aggressive approach or if you run into actual issues with this version, you can try Better GC instead. But so far there don't seem to be any serious issues known. Aggressive mothballing can cause hediffs on worldPawns not to progress as intended, which can always lead to weird and unintended behaviour. Usually that results in minor inconsistencies and nothing gamebreaking though.
After Rocketman's author quit modding RimWorld, some attempts have been made by random people to continue the mod. None of them ended in a viable product though. Not until ViralReaction recently picked it up, removed obsolete methods and is now converting the rest into a successor, now known as "Missile Girl."
Features still relevant and not made obsolete by the 1.6-update cover def-caching (speed up game-initialization,) stat-caching and alert-throttling. Additionally, some of the previously removed optimizations from Performance Analyzer have been added
(deep-drill-improvements, temperature checks, etc.)
The mod is not officially released as of the time writing, but already available via Github. Initial testing for some time hasn't shown any issues so far - so we decided to already include it here.
PSA: Same as Rocketman before - make sure to always load Missile Girl dead-last in your loadorder!
While most features for actual performance-enhancement were removed/disabled from Performance Analyzer a while back, the mod still is essential to locate and analyse the source and reason for performance-loss. So technically not fitting the criteria of this list, it still should be mentioned here for the sake of completeness.
Since it's usage is a bit advanced and interpreting the readings quite a complex topic, we recommend checking in on Dubs Discord and to read the user-guide in the #analyzer-guide channel.
Focused on improving the generation of quests for large modlists. Still some more feedback needed to really say how useful it is and the assumption so far is that it only will make a relevant difference in extreme cases - but so far also no issues reported that were caused by it.
Similar like the (now disabled) optimizations in Performance Analyzer and (now available) in Missile Girl. This mod's approach might be a bit more impactful than the other methods - but it's unclear if this difference would ever become relevant in a real scenario. Can be used on top of Missile Girl if you want, but don't expect too much.
Similar to Deep Drill Optimizer, the impact of this mod on TPS is questionable. Preliminary numbers on realistic scenarios have been too small in difference to really suggest a big improvement - but it also doesn't seem to hurt. For those who need every single TPS to keep their game afloat.
The classic and reason for much confusion in the community for years. The basegame's 'colonist bar' is quite heavy on performance, like most UI elements in RimWorld are. CCMB replaces the vanilla method with a significantly faster one, but is constantly mistaken for being a heavy mod - because of that, here's a bit of insight.
When measuring the impact of mods, Performance Analyzer tends to show CCMB being quite high. This is misleading though; the vanilla method it replaces would be way worse. It's just that it wouldn't show up in the measurment if not patched by something. So even while high on the list, it still is a net-improvement for performance.
Similar applies to Colony Groups (linked below) which builds on top of CCMB. When measuring, you more or less have to subtract the impact of the colonist bar (vanilla or CCMB) from Colony Groups to get its actual impact. Both mods are meant to be used together. CCMB will improve the UI element in general and Colony Groups allows you to hide pawns in groups as your colony grows, improving things further.
The following mods are still new or need testing otherwise before being considered to be recommended. So use them at your own risk if you want, and maybe even report to us or people on Dubs Discord if you have some hands-on experience with them - no matter if positive or negative. We only put mods here that at least passed a first assessment - so they likely will end up good even if they're not there yet - but otherwise don't consider them adequately vetted.
HAR Unpatcher
(Safe. Needs to be properly integrated into this list)
Ideo Tick Optimization
(Skips ticks for empty faction Ideos)
Gear Stat Optimization
(Similar to Missile Girl's stat caching. Has to be checked if actually needed when using MG, or if this kind of optimization could potentially be (re-)added to it.)
RimThreaded
Rim73
RuntimeGC
Any kind of save-cleaner or
save-shrinker is always a risk!