Lightroom Classic is slow, but Lightroom is fast.

That is indeed weird. There really should be very little difference in performance between Classic and Cloudy as well as ACR. The only real difference should be perhaps interface differences such as how fast switching from Library to develop feels but not the actual operation of the interface such as creating masks. Seeing that you get vast differences between CPU and GPU occupation between the different programs really means that there is a difference in code paths being used which is very unexpected and points to some kind of bug

Lightroom Classic version: 13.0 [ 202309270914-5a1c6485 ]
License: Creative Cloud
Language setting: en
Operating system: Windows 11 - Business Edition
Version: 11.0.22621
Application architecture: x64
System architecture: x64
Logical processor count: 20
Processor speed: 3.5GHz
SqLite Version: 3.36.0
CPU Utilisation: 0.0%
Built-in memory: 130755.8 MB
Dedicated GPU memory used by Lightroom: 100.2MB / 11041.0MB (0%)
Real memory available to Lightroom: 130755.8 MB
Real memory used by Lightroom: 4098.5 MB (3.1%)
Virtual memory used by Lightroom: 4482.3 MB
GDI objects count: 815
USER objects count: 3171
Process handles count: 2302
Memory cache size: 0.0MB
Internal Camera Raw version: 16.0 [ 1677 ]
Maximum thread count used by Camera Raw: 5
Camera Raw SIMD optimization: SSE2,AVX,AVX2
Camera Raw virtual memory: 1060MB / 65377MB (1%)
Camera Raw real memory: 1064MB / 130755MB (0%)
System DPI setting: 144 DPI (high DPI mode)
Desktop composition enabled: Yes
Standard Preview Size: 5120 pixels
Displays: 1) 5120x2160
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 2080 Ti (31.0.15.3758)
Init State: GPU for Export supported by default
User Preference: Auto

Application folder: C:\Program Files\Adobe\Adobe Lightroom Classic
Library Path: C:\Users\chaos\Pictures\Lightroom\Lightroom Catalog-2-v16.lrcat
Settings Folder: C:\Users\chaos\AppData\Roaming\Adobe\Lightroom

Installed Plugins:

Config.lua flags: None

Adapter #1: Vendor : 10de
Device : 1e07
Subsystem : 866a1043
Revision : a1
Video Memory : 11041
Adapter #2: Vendor : 1414
Device : 8c
Subsystem : 0
Revision : 0
Video Memory : 0
AudioDeviceIOBlockSize: 2048
AudioDeviceName: $$$/dvaaudiodevice/SystemDefaultAndEffectiveDeviceName=System Default - Динамики (iFi (by AMR) HD+ USB Audio)#{comment}DVAAU-4201250: Open the audio hardware preferences page.
AudioDeviceNumberOfChannels: 2
AudioDeviceSampleRate: 192000
Build: LR5x83
Direct2DEnabled: false
GL_ACCUM_ALPHA_BITS: 16
GL_ACCUM_BLUE_BITS: 16
GL_ACCUM_GREEN_BITS: 16
GL_ACCUM_RED_BITS: 16
GL_ALPHA_BITS: 0
GL_BLUE_BITS: 8
GL_DEPTH_BITS: 24
GL_GREEN_BITS: 8
GL_MAX_3D_TEXTURE_SIZE: 16384
GL_MAX_TEXTURE_SIZE: 32768
GL_MAX_TEXTURE_UNITS: 4
GL_MAX_VIEWPORT_DIMS: 32768,32768
GL_RED_BITS: 8
GL_RENDERER: NVIDIA GeForce RTX 2080 Ti/PCIe/SSE2
GL_SHADING_LANGUAGE_VERSION: 4.60 NVIDIA
GL_STENCIL_BITS: 8
GL_VENDOR: NVIDIA Corporation
GL_VERSION: 4.6.0 NVIDIA 537.58
GPUDeviceEnabled: false
OGLEnabled: true
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