Memory usage keeps blowing up without adding particles?!

So I have this elaborate scene which is already pretty heavy with two particle systems growing trees and shrubs.

I just added another particle system (ivy gen) to grow some nice looking ivy on a wall. My memory usage jumped from 7.xx GB to now over 12GB! Not at one time though.

Here is what happened:

Added ivy gen, no leaves. Transformed to mesh so I could add own particle system. Modeled own leaves. Added that… I think by that time the scene grew to around 8GB from 7.

Then I used weight paint to distribute the leaves. It seems like that just before that everything has become extremely unresponsive.

Whenever I paint a new weight to keep distributing not only takes it several seconds to update, every time memory usage increases significantly. I don’t get it… by weight painting I’m only distributing the same amount of particles, I’m not adding new ones… why does that happen, makes no sense to me. Going in and out of object/Weight paint also takes several seconds (only for ivy though).

I have a very beefy PC, 16core, 64GB RAM, RTX2070 super so I’m kinda shocked to see this ivy gen particle system completely killing it… before it was very manageable.

Considering to just delete the whole thing and do something else instead of ivy.