Champions of Norrath slowdowns despite very good PC

[daedrixxx]

I'm encountering pretty bad slowdowns with this game (yes, I know it's a heavy one to emulate) inside the Goblins' Caves near the beginning of the game. 
I read that it used to have slowdowns in caves, near fires, and whenever there was a large number of enemies on screen, but that was supposedly been patched with the latest dev builds.
I update automatically, so my ver is always the latest, and ofc I've applied both Disable Partial Invalidation and Texture Preload on Partial, and I use Vulkan.
Yet, in caves, especially when I'm near huge black chasms (even without fires or enemies), the game loses like 20% performance, going from 50fps (PAL ver) to 40fps.
My PC should be more than enough to run this game at 4K, for I have an i9 9900k, RTX 3080 10GB and 32 GB of RAM.
I aim for x6 internal res, but thinking that the too high res could have been causing the problem I lowered it first to x3, then to native res, but curiously the game performed MUCH worse!
At native res it was barely playable anywhere, let alone in the problematic areas. I think that could be due to all the heavy work being left to the CPU at lower res, while upping the res the GPU takes over.
At native res I noticed what's going on in greater detail: when severe frame drop happens the screen flashes black for an instant and the interlace method seems to change, the image becoming "blurrier" for some time before returning sharp.
I tried with v-sync on and off, applied the de-interlace patch (that actually makes the image blurrier and made no change), but the only thing that somewhat "works" is to up the EE cycle rate to 130, 180, or 300%. The black flashes appear much more sporadically as the cycle rate goes up, but the frame drops still happen.

So, what could be causing this? Is there a fix I can apply somehow or is it a case of the emulator just "not being there yet"?

[jesalvein]

care to show the OSD statistics when you get slowdowns ?

[daedrixxx]

care to show the OSD statistics when you get slowdowns ?

Yes. Sorry, I should've mentioned that I'm using the qt-avx2 build, so no OSD, and I cannot seem to find the way to generate a log.
But I've made some other tests...
First, I forgot to mention that when the slowdowns happen, and the screen flickers black, some textures at the borders of the screen disappear.
I also found out that I was supposed to switch to software mode, not native res, to make the game run as close to a real PS2 as possible and get no slowdowns... But that kinda defeats the purpose of playing on an emulator now, doesn't it?
Most importantly, I casually switched to OpenGL and, to my surprise, that seems to fix any slowdowns for me. I also need 300% EE cycle rate though. Anything lower and I still get the slowdowns and the black flickers.
These, I discovered while playing windowed, happen as soon as I lose even 1 fps (i.e. from 50 to 49), while they don't happen when the game hitches for a moment (I suppose to load from the HD) when the framerate plummets all the way down to the 30's for an instant.
This is strange... in the two Baldur's Gate I got noticeable slowdowns with OpenGL (default EE cycles), while with Vulkan they run at full speed at x6 internal res.
Indeed in this game with OpenGL at default EE cycles the main menu runs in slow-mo, but at 300% cycles everything seems fine so far (played again from the beginning till the area I was getting slowdowns before).
Are there any contraindications in playing with overclocked EE cycles?

[jesalvein]

Yes. Sorry, I should've mentioned that I'm using the qt-avx2 build, so no OSD, and I cannot seem to find the way to generate a log.

oh, ok. First time using pcsx2, i guess....
lemme help a bit :

and

But I've made some other tests...
First, I forgot to mention that when the slowdowns happen, and the screen flickers black, some textures at the borders of the screen disappear.
I also found out that I was supposed to switch to software mode, not native res, to make the game run as close to a real PS2 as possible and get no slowdowns... But that kinda defeats the purpose of playing on an emulator now, doesn't it?

unlimited memcards, savestates, cheating system... not really.

Most importantly, I casually switched to OpenGL and, to my surprise, that seems to fix any slowdowns for me. I also need 300% EE cycle rate though. Anything lower and I still get the slowdowns and the black flickers.
These, I discovered while playing windowed, happen as soon as I lose even 1 fps (i.e. from 50 to 49), while they don't happen when the game hitches for a moment (I suppose to load from the HD) when the framerate plummets all the way down to the 30's for an instant.
This is strange... in the two Baldur's Gate I got noticeable slowdowns with OpenGL (default EE cycles), while with Vulkan they run at full speed at x6 internal res.
Indeed in this game with OpenGL at default EE cycles the main menu runs in slow-mo, but at 300% cycles everything seems fine so far (played again from the beginning till the area I was getting slowdowns before).
Are there any contraindications in playing with overclocked EE cycles?

whoooofffff.
revert all settings to default and set renderer to automatic
then increase internal res gradually until you find a sweetspot. fiddling with settings and EE cycle rate when you are an absolute beginner is a bad idea, really.

[daedrixxx]

No, I'm not a first timer. It's just that I use PCSX2 for short bursts, like finishing a game, and then forget about it for a long time.
In fact, it's the first time I use the new interface, but I've used this emulator since 2007 at least, and I know how to navigate most of the menus and what the various settings do...
I may not be IT level, but I know how to use this emu.

So, here's the log:

Code:

[  178.7270] Searching for a BIOS image in 'D:\Emulators\PCSX2\bios'...
[  178.7586] Bios Found: Europe  v01.60(04/10/2001)  Console
[  178.7593] Using BIOS 'D:\Emulators\PCSX2\bios\PS2 Bios 30004R V6 Pal.bin' (Europe  v01.60(04/10/2001)  Console Europe)
[  178.7593] Allocating memory map...
[  178.7594] Opening CDVD...
[  178.7766] isoFile open ok: D:\Emulators\roms\Sony - PlayStation 2\Champions of Norrath (Europe) (En,Fr,De)\Champions of Norrath (Europe) (En,Fr,De).iso
[  178.7766] Image type  = DVD
[  178.7889] isoFile: second layer found at sector 0x001fb230
[  178.7889]  * CDVD Disk Open: DVD, Double layer:
[  178.7889]  * * Track 1: Data (Mode 1) (4161600 sectors)
[  178.8008] Opening GS...
[  178.8052] Vsync is ON
[  178.9511] Created a OpenGL context
[  179.0883] OpenGL Graphics Driver Info:
[  179.0884] OpenGL Context:
[  179.0884] 4.6.0 NVIDIA 516.94
[  179.0884] NVIDIA Corporation NVIDIA GeForce RTX 3080/PCIe/SSE2
[  179.0892] 1 program binary formats supported by driver
[  179.1358] Read 915 entries from 'D:\Emulators\PCSX2\cache/gl_programs.idx'
[  179.1358] Using hardware for point expansion.
[  179.2583] Vsync is ON
[  179.2585] Opening SPU2...
[  179.2589] Initializing SndBuffer at sample rate of 48000...
[  179.6547] (Cubeb) Using normal 2 speaker stereo output.
[  179.6576] (Cubeb) Minimum latency: 10.00 ms (480 audio frames)
[  179.7668] Opening PAD...
[  179.7668] Opening DEV9...
[  179.7700] Opening USB...
[  179.7700] Opening FW...
[  179.7703] McdSlot 0 [File]: D:\Emulators\PCSX2\memcards\Mcd001.ps2
[  179.7876] McdSlot 1 [File]: D:\Emulators\PCSX2\memcards\Mcd002.ps2
[  179.7987] EE/iR5900-32 Recompiler Reset
[  179.8394] Searching for a BIOS image in 'D:\Emulators\PCSX2\bios'...
[  179.8397] Bios Found: Europe  v01.60(04/10/2001)  Console
[  179.8397] Using BIOS 'D:\Emulators\PCSX2\bios\PS2 Bios 30004R V6 Pal.bin' (Europe  v01.60(04/10/2001)  Console Europe)
[  179.8399] Bios Found: Europe  v01.60(04/10/2001)  Console
[  179.8730] BIOS rom1 module not found, skipping...
[  179.8730] BIOS rom2 module not found, skipping...
[  179.8730] BIOS erom module not found, skipping...
[  179.8863] VM subsystems initialized in 1171.59 ms
[  179.8863] [GameDB] Has not been initialized yet, initializing...
[  179.9449] [GameDB] 11307 games on record (loaded in 58.49ms)
[  179.9449] [GameDB] Searching for '' in GameDB
[  179.9449] [GameDB] Could not find '' in GameDB
[  179.9449] Applying settings...
[  179.9450] [GameDB] Searching for '' in GameDB
[  179.9450] [GameDB] Could not find '' in GameDB
[  179.9451] Processor count: 8 cores, 16 processors
[  179.9451] Cluster count: 1
[  179.9451] Ordered processor list: 0, 2, 4, 6, 8, 10, 12, 14, 1[SMT 1], 3[SMT 1], 5[SMT 1], 7[SMT 1], 9[SMT 1], 11[SMT 1], 13[SMT 1], 15[SMT 1]
[  179.9832] MTVU speedhack is enabled, saved states may not be stable
[  180.1331] Loading SPU2
[  180.1413] Loading PAD
[  180.1414] Loading GS
[  180.1555] (SYSTEM.CNF) Detected PS2 Disc = cdrom0:\SLES_523.25;1
[  180.1555] (SYSTEM.CNF) Software version = 1.02
[  180.1555] (SYSTEM.CNF) Disc region type = PAL
[  180.2808] ELF (cdrom0:\SLES_523.25;1) Game CRC = 0x75D86958, EntryPoint = 0x00100008
[  180.2809] [GameDB] Searching for 'sles-52325' in GameDB
[  180.2809] [GameDB] Found 'sles-52325' in GameDB
[  180.2809] Loading game settings from 'D:\Emulators\PCSX2\gamesettings\SLES-52325_75D86958.ini'...
[  180.2811] Applying settings...
[  180.2813] [GameDB] Searching for 'sles-52325' in GameDB
[  180.2813] [GameDB] Found 'sles-52325' in GameDB
[  180.2813] [GameDB] Manual GS hardware renderer fixes are enabled, not using automatic hardware renderer fixes from GameDB.
[  180.2813] [GameDB] Enabled GS Hardware Fix: texturePreloading to [mode=1]
[  180.2813] Updating GS configuration...
[  180.2813] Vsync is ON
[  180.2813] [GameDB] Searching for 'sles-52325' in GameDB
[  180.2813] [GameDB] Found 'sles-52325' in GameDB
[  180.2813] [GameDB] Searching for patch with CRC '75D86958'
[  180.2813] [GameDB] No CRC-specific patch or default patch found
[  313.2503] (VMManager) Pausing...
[  315.9689] Decommitting host memory for virtual systems...
[  316.0150] Releasing host memory maps for virtual systems...
[  316.0150] Releasing host memory maps for virtual systems...

In regards to the OSD stats I see numbers with letters beside them, such as: 42200 P | 670 D | 690 DC | 13 B | 20 RB | 1 TC | 180 TU

These stats (except fot 1 TC that remains the same) get hammered down when the problem occurs, like P becomes 30-25000, D and DC go in the 400s, but B and RB can go up to the 90s before returning to the normal range.
I hope this is the data you were asking for

[daedrixxx]

So... found anything yet?

You could have at least reported back if the OSD statistics I posted almost a month ago were of any use, since it was you that asked for them in the first place @jesalvein