When applying the add stroke blending effect the RAM usage of Krita skyrockets from the normal 800-900mb to a huge 2.5gb of ram and disabling it just makes it go down to 800-900mb again.

Although i don't have large amounts of ram this doesn't affect the performance of my PC overall but really makes krita run painfully slower, and just turning on and off the FX options seem to magically restore the performance so i think that's the problem?

The resolution of the canvas i was using was regular 6k (6144x3072) while using the D3D11 drawing. If there is any other factor that could cause this i could reply with any other setting that i have on.

My PC specs:
OS: Windows 7 64 bits, 6gb of RAM, Nvidia 740 2GB DDR3 OpenGL 4.4, AMD Athlon x4 640

Could you make a bug report with the .kra file attached?

Sure, sadly i had to cancel the entire painting because the performance was so crippled i could barely save the file or even access its auto save, it was really bad, I've been having the same problems with another painting this time with 4000x4000 resolution, luckily i was able save it so it'll be posting that one instead.

And as heads up, this one has less layers and content overall, i would say the problems i was experiencing with the 6k one were at least twice as bad.