Version 9 is slower in general than v8, especially for viewing PSDs

[AmeJunn]

System information

• Windows OS version: Windows 10
• ImageGlass version: 9.1.8.723 (64-bit)
• ImageGlass release: Store / Classic? Classic

To Reproduce

PSD slowness:

1. Have a folder with a bunch of PSDs
2. Browse through them

Slowness to go to next/previous image after opening the program

1. Open an image
2. Go to the next/previous image (preferably one that is 1mb or bigger)

• Also compare with version 8.0.12.8

Actual behavior

It's very slow and uses a lot of CPU. If the PSDs are bigger than about 300mb it takes several seconds to load the image.
Program seems to need some "warming up" to get it's speed. After some moments it's has the expected speed (except when browsing PSDs)

Expected behavior

Should be faster. I used to use an older version and it loaded things pretty much instantly. I tried downloading version 8.0.12.8 again to test and it did everything very very quickly. It had no problems loading PSDs and no need to "warm up". It would be fast from the first moment it opens. Version 9 seems much slower. Also I downloaded the EoL version for version 8 and it also struggled with PSDs. So somewhere along the updates for ImageGlass it started struggling with PSDs when before it didn't.

Additional context

• I turned off asynchronous loading and it made things a tad faster, but for the PSD load time it's still very slow;
• That older version (8.0.12.8) only displayed 1 frame in the frame navigator (P) when viewing PSDs, while the newer versions displays multiple frames for the PSDs. Maybe this is the culprit for slow PSD viewing? Is it trying to read every layer and that's why it's slower?
• I set the number of cached images in the image booster to 1 and to 10 and it made close to no difference. But 10 was faster for me;
• Increasing maximum file size cache has made things faster, but still not as fast as version 8.0.12.8;
• Folder size could be a factor for slowness aswell. A folder with 1k images seems to be slower than a smaller folder.

But to be honest the "warming up" is a smaller issue for me. It's not that big of a problem. BUT the PSD load time is unusable at times. I have to keep a portable version of v8 in my computer to browse some of my PSD folders.

I love this program and It's so close to perfection for me

[AmeJunn]

Going to add one more slowness problem that wasn't present on v8, but is in v9:

When first going to next/previous image after opening one it takes longer to load the next/previous image. Doesn't matter how long I wait, I could do it immediately after opening the image or waiting several minutes, the first next/previous is much slower than all subsequent ones. After the first next/previous they are all much faster. It's just that first one that's slower for some reason.
In version 8 it would just go to the next/previous image instantly, not mattering if it was the first image after opening or not.