How can I render thousands of jigsaw pieces? (sprites and masks)

[nanal49301]

I'm trying to make a jigsaw puzzle game for larger amount of pieces.

I make every piece of puzzle with sprite and geometry mask. Everything seems fine when I render 1000 or 10000 sprites, but when I attach mask, it's too laggy, and unplayable. Geometry mask is needed because of the real jigsaw shape.