Block updates, especially pistons and observers, causing lag

Block updates, such as pistons, observers, and other redstone components, cause noticeable amounts of lag. Attached are some screenshots.
As you can see, when the piston isn't moving, I have around 60 frames. When I create a simple observer clock to update that piston, my frames are cut in half.
To recreate:
Create a new world
Create a redstone clock, or any mechanism that repeatedly updates a block.

Yes, I'm well aware this is a duplicate, but seeing as the original issue didn't have screenshots attached and wasn't very well documented, I thought I'd provide a bit more information. Hope it helps :/