P: Sampling lag and stutter with either clone stamp or healing brush

wow! this post is from 2020 and adobe didn't fix this problem yet. I bought a Gaomon M10K pro pen tablet and I have the clone stamp issue. it is lagging a lot, but only with the pen. it works fine with the mouse. I was about to return the tablet, but looks like even the wacom tablets are having the same issue. 

"If you disable rulers, or go to Preferences > Technology Previews... and disable "Enable Native Canvas Rulers" and restart Photoshop, does it work better?"

This worked!!! Thank you! I was also able to turn my graphics processor back on in the performace section as well once i disabled "Enable Native Canvas Rulers"
Thanks again!! Now i can get back to work!

@firstl56309848 

Couple of things to try:

Use the following optional extension (see this kb article for info on optional extensions) in PSUserConfig.txt: 

sprk 200

The time value above reflects the time for which a key needs to be pressed to enable the spring-loaded feature

Start with 200, and try 100 or 300 to see if 200 doesn't work. We found that 100 to 300 works well most customers. 

If you disable rulers, or go to Preferences > Technology Previews... and disable "Enable Native Canvas Rulers" and restart Photoshop, does it work better?

This does not work for me. I have Photoshop 23.2.1 and get the exact same lag when holding ALT down while tryinng to use the stamp tool.. Very annoying and hard to work. 

Thank you for confirming the fix.  We still have a bug where the Preview severely lags if Rulers are enabled - we're working on a fix for that. 

I am coming with an update on this thread, after updating to the latest version, Adobe Photoshop Version: 22.4.0 20210512.r.195 5b318a5  x64, the lag seems to have disappeared. Still testing it out, but working on 100%-200% zoon in 9000k+ pixel images that have many layers seems pretty fluent right now.

@Christian Schranner DUDE!!!  I've been struggling with this damned lag problem for a few years now and your suggestion worked for me!  I went into Device Manager and realized that I had both my Nvidia GT730 and onboard graphics cards working together and when I disabled my motherboard graphics driver...POOF!   Gone is the lag!  The litmus test was leaving photoshop running in the background for an hour or so, coming back to restart my editing and it is still working like new....smooth and absolutely no lags!  Not sure if this applies to a lot of you, but I'm sure it will help a lot of folks out there who may be having this sort of problem with PS and other programs as well.   Thanks Christian!

Indeed going full screen solves it. Still not a solution tho.

before i solved it with disable the second graphic card, i always used fullscreen-mode while retouching (by press "F" two times). in this screen mode i dont had any problems with laggy photoshop.

maybe try this