I recently updated my Lightroom CC version and when using the adjustment brush (with and without overlay) Lightroom becomes incredibly slow or even unresponsive. Not only that but it produces brushstrokes I never did i.e. I will use the brush on one area and then stop to wait and see before the strokes I made fill in, for what seem to be 10-20 seconds on average, which by itself is completely unacceptable, and then Lightroom proceeds to make a big random stroke over areas I never even hovered over let alone brushed in. Then, as I go on to erase that random erroneous stroke, the problem repeats in that it removes not only the error, but also a portion of what I just filled in. What used to be a 5 minute edit, tops, is now an hour long ordeal with mediocre results at best. Thus far I tried updating drivers, changing the cache size, giving the Lightroom Process a higher priority with so many restarts I think my power button is about to fall off. My computer has 32 GB Ram, a 5930K i7, EVGA GTX 980Ti, with m.2 and reg. SATAIII SSDs. running windows 10 Pro. From many years of running older versions of Lightroom on a Early 2009 Mac Pro and Mid 2014 MacBook Pro I am more than confident that I have enough resources in my machine to smack lightroom dead many times over, and sure enough when I check my task manager I can see that lightroom barely scratches 10% on my CPU and at best it went up to 4.4 GB of RAM at which time it was unresponsive. As far as I can tell my computer doesn't register any heavy loads in any of its components as all of it stays nice and quiet.
Any help on this issue would be much appreciated: How do I get Lightroom to use more than 10% of my resources? How can I get the adjustments brush to work? Is there any way to downgrade to let's say LR4 or LR5? Any help to improve this mess so I can actually finish my work.
P.S. Photoshop, Illustrator, InDesign, Brackets, Hasselblad Phocus (just to Test) all work fine without any freezing or input problems.
Please turn off the Graphics Processor from Lightroom preferences.
Go to Lightroom Preferences from the Edit menu
Click on Performance tab
Uncheck the Graphics Processor
Let us know if that helps.