Since maybe a month back, curves performance in lightroom has become so slow and unresponsive that it's nearly useless. I usually export to photoshop when I use curves, so it didn't bother me too much when the problem began, but it's worsening and i'm starting to worry about what the problem might be. Basically it takes maybe half a second to react to my mouse or Wacom movements, and takes a second or two to show the result. It makes the process painfully slow.
I have no performance issues with any other tool (maybe the brush tool with a very large and smoothed brush, but everything else run smoothly), and curves runs fantastic in photoshop, so it's just a lightroom problem.
Any ideas of what might be happening?
Lightroom updated to the last version (2015.5)
AMD 1090T (6x3,2Ghz)
256 SSD+ 2TB HDD
SO and all drivers up to date.
Please try and turn off the Graphics Processor from the Lightroom preferences.
Go to Lightroom Preferences from the Edit menu
Click on Performance tab
Uncheck the Graphics Processor
Let us know if that helps.
I definitely have an improvement in performance when playing with curves with gpu processing unchecked, but it's still far from smooth, and though curves performs better, everything else gets slower (exposure, contrast.. etc.).