LrC extremely slow, and only use GDDR not DDR

[LOMOLCW]

In the system info, it says: Real memory available to Lightroom: 65434.4 MB

However, My  graphic ram is 6gb grtx 2060, my computer memory is 64GB, not sure how I can adjust the physical momory in 'performance' tab.

when i do any local adjustment, it just takes too much time. changing the size of brush will take 54-10 seconds. holding alt to use eraser takes 5-10 seconds too.

When i check my resource monitor, it shows the same thing: LrC uses 7gb of ram, and all graphic memory (about5-6gb), when I close the LrC, the graphic ram drops immidietly.

Lightroom Classic version: 9.4 [ 202008061458-dbb2971e ]
License: Creative Cloud
Language setting: en
Operating system: Windows 10 - Business Edition
Version: 10.0.19041
Application architecture: x64
System architecture: x64
Logical processor count: 12
Processor speed: 3.4 GHz
SqLite Version: 3.30.1
Built-in memory: 65434.4 MB
Real memory available to Lightroom: 65434.4 MB
Real memory used by Lightroom: 3627.8 MB (5.5%)
Virtual memory used by Lightroom: 3975.1 MB
GDI objects count: 838
USER objects count: 2928
Process handles count: 1894
Memory cache size: 115.7MB
Internal Camera Raw version: 12.4 [ 555 ]
Maximum thread count used by Camera Raw: 5
Camera Raw SIMD optimization: SSE2,AVX,AVX2
Camera Raw virtual memory: 1982MB / 32717MB (6%)
Camera Raw real memory: 2004MB / 65434MB (3%)
System DPI setting: 96 DPI
Desktop composition enabled: Yes
Displays: 1) 1920x1080, 2) 1920x1200
Input types: Multitouch: No, Integrated touch: No, Integrated pen: Yes, External touch: No, External pen: Yes, Keyboard: No

Graphics Processor Info:
DirectX: NVIDIA GeForce RTX 2060 (27.21.14.5167)

[dj_paige]

"when i do any local adjustment, it just takes too much time. changing the size of brush will take 54-10 seconds. holding alt to use eraser takes 5-10 seconds too."

A common problem. Your CPU is not fast enought to do all the calculations and make the response appear instantaneous. Memory is not the problem. Your possible workarounds are:

1) Turn OFF the Graphics Processor use in Lightroom

2) Do all of the lens corrections and transforms in Lightroom as the last editing step, after you have done the local adjustments

3) Do the local adjustments in Photoshop

4) Get a faster CPU

[LOMOLCW]

thanks for your input.

my cpu usage is rarely at 100%, even when it was extremely slow, it was only using 10-20% of cpu capacity.

my memory on my graphic gard is however, full. when i turn off the gpu option, my performance is still limited. I have a lot of resources with ram and cpu that is not utilised by LrC and the program itself is still slow.

[dj_paige]

Since you have 1920x1080 (or 1920x1200) monitors, your GPU should be turned OFF in Lightroom. But if that doesn't help, then this is a common problem that lots of brushing and/or lot of spot healing on an image causes Lightroom to slow down. More memory will not help.

[LOMOLCW]

Could you elaborate why at this resolution I should turn off GPU?

Excuse me if I don't trust your answer, as the first answer you did was incorrect. You suggest me to buy a new cpu, yet not one core of my current one is at full capacity (6core i7 unlocked).

The bottleneck that I can see, is the memory on my graphic card, when i shut down LrC, that goes down immidietly. And when I check the LrC system info, it shows 6GB only (when I have a lot more system memory installed). this 6GB cap exist whether i turn on or off GPU processor on my LrC. And there is no way in LrC that I can make adjustment.

[dj_paige]

GPU turned has a trivially small impact on most operations with a 1920x1080 monitor, but a few operations, such as brushing and spot healing are slowed down when the GPU is on. So, no benefit, but definite drawback, to have GPU on with a 1920x1080 monitor.

[dj_paige]

Should have said "GPU turned ON has a trivially small ..."

[GoldingD]

In Catalog Settings, File Handling. What do you have set for standard Previews?