Blender big problem. Memory leak.

Guys i have really big problem with i think i find really some bug or it is just my PC… but i don;t think so…

If you remember me i am working on scene with planes… and mostly all was okey i started adding detail to planes etc… i have 6 gigs of ram… Blender showss me that in viewport it is only using 150 of ram… Then while rendering this is going up to 250 memories… and in middle of render The ram usage go to 100% and SWAP ram go to 100% too… but blender is still rendering neverminding that the whole computer just go slow as hell.

Any suggestions whats wrong with this? I reinstaled blender however i didn’t reset the settings to default. and another think it dose not happen in 100% mostly somethink about 70%

! i got where is the problem problem is in compositor if i render those layrs speratly i mean scene one i render being on scene one it is okey then i do the same in scene two… however if i create new scene and in sompoting i will put 2 scenes to render… as i was doing and i think many people… the blender have big memory leak.

I think I might have a similiar problem. Blender says 660 mb usage but when I look at the operating system. It’s saying 2 gigs to 2.7 gigs. I’m not certain if its a hardware or operating system problem which I doubt. My components are up to date.