It works fine for any particle count from 100,000 below, but with more than 100,000 particles (I've set max particle count to one million), I get this artifact in the particle age map, like the particle age is offset in the beginning.... look at the image. It's as if the particles start at age 90%, go to 100%, then snap to 0%, and then go up to 90% again, where they die. (the offset error gets worse the more particle I use)
EDIT: actually, they don't snap to 0, it looks like they snap back to where they SHOULD be at that certain time, and then continue correctly to 100...)
I get the same result if I render another frame in the timeline, meaning it's not something that happens at a specific point in time, it's all particle's age that's offset.
Thanks for any help.