Why is the surface blur so slow?

[Jqqerry]

I usually use a lot of Dust/Median from noise tabs and Gaussian blur.

I don't remember how slow it was when I used Surface blur a few years ago, but I found it slow while trying something new now.

It's less slow if you just apply a filter without using a smart object, but it's not as fast as other filters.

I don't know if you need to set up my Photoshop function, but I'll write it down below.

History : 80

Cache Level : 4

Cache Tile Size : 1024K

Memory : 80%

Scaracth Disk : 250Gb SSD Full Storage for only photoshop scrach disk

Use Graphic processor : check 1060

drawing mode : advanced 

Check : Use Graphics Processor to Accelerate Computation

            Use Open CL

            Anti-alias

UnCheck : 30bit display

What i have to do? I don't know what the problem is.

[c.pfaffenbichler]

What are the Pixel dimensions, bit depth, color mode, … of the image? 

[Jqqerry]

every image is diffrent, but the almost same loading time.

mostly 3000x4000 px , 8 or 16bit, Srgb

[c.pfaffenbichler]

It seems the Filter does not utilize the GPU 

https://helpx.adobe.com/photoshop/kb/photoshop-cc-gpu-card-faq.html#Tested%20video%20cards%20for%20P...

so I guess you are stuck with trying to improve general perfomance: 

https://helpx.adobe.com/photoshop/kb/optimize-photoshop-cc-performance.html

For example I personally fund 80 History Steps to be quite a lot …