yea this happens to me, here is the error i get on the devlog

Exception in RimWorld.ThinkNode_ConditionalColonist TryIssueJobPackage: System.NullReferenceException: Object reference not set to an instance of an object
at (wrapper dynamic-method) RimWorld.ThinkNode_ConditionalNeedPercentageAbove.Satisfied_Patch1 (object,Verse.Pawn) <0x0006f>
at Verse.AI.ThinkNode_Conditional.TryIssueJobPackage (Verse.Pawn,Verse.AI.JobIssueParams) <0x0002b>
at Verse.AI.ThinkNode_Priority.TryIssueJobPackage (Verse.Pawn,Verse.AI.JobIssueParams) <0x00130>

I have the same problem now, it didn't happen before. Any idea of a possible solution? Is this a mod conflict?

Same problem. Can't believe it's still a thing.

Same problem right now

Have the same problem and its really annoying cuz as much as i love this mod that one thing constantly makes me reconsider having vampires as my colonits.

Used this mod for a while now, same issue. It's caused by the "avoiding sunlight" AI, always happens at 5pm (when vampires wake up but still can't go outside) and at 6am when the sun rises and any vampire is not near their coffin.
Also happens anytime a vampire is "stuck" outside with no clear path home.

The pathfinding in this mod is flawed. so is the priority of "jobs" given, like feeding on anything. for some reason it's set as emergency task and takes priority over literally everything else, so vampires will usually not immediately respond to any command you give them (including a better alternative to feed on), queueing it up instead.
Both of these cause insane lag spikes, especially when you have more than one vampire.

Yeah, I love the premise of the mod, the WoD theme etc. And I'm not going to complain about being able to play a free vampire mod, but objectively speaking, this mod is put together very, very poorly. Cults and Vampires are two of my favorite mods, but I almost never use them, because while they start off fine, they inevitably turn my mid/late game colonies into chugging messes begging for the sweet release of death.

I honestly hope a skilled modder will come along and (re)create vamps & cults someday, while not being discouraged that these mods already exist. These could genuinely do with being surpassed and retired, it pains me to say it.

I am playing on a world with a permanent eclipse so found a simple solution; set the AI behaviour that controls what the vampire does to avoid light to 'No AI'. That stops the lag completely for me.
I haven't tried this, but if not in a permanent darkness world you could also maybe setup a 'vampire' zone that only lets them access part of the map which may cut down on whatever pathfinding job is being spammed.

Originally posted by GypsyFlip:

set the AI behaviour that controls what the vampire does to avoid light to 'No AI'. That stops the lag completely for me.

I found that setting once, No idea what I set it as, and cannot find it again. Do you happen to know which menu it's in?

If i remember correctly its in the "needs" Tab, there should be and icon of the sun and you have to press it until it changes to "no AI"

Has no one fixed this? I hate to sound entitled but it surprises me no one has made a patch for it with how many skilled modders are in this community.

If you turn the Avoid-Sunlight-automatik,off [No Ai] -> in the Bio-Vampire-skill-sheed (right side, from the discipline Writing) the lags are gone ^^ ähm...on my pc ^^

Major lag when auto avoid sunlight is on even on a single vampire pawn, sometimes even get a notification "Rimworld is not responding". When set to no AI everything is fine tho, also seems to lag less during night time even while auto avoid sunlight is on.

Originally posted by OneShotPaddy:

Has no one fixed this? I hate to sound entitled but it surprises me no one has made a patch for it with how many skilled modders are in this community.

Yeah. Hard to believe the same problem has been around for multiple years.