Deathsmiles on lr-mame2015 : Any performance tips?

roslof

This looks freshly updated:
https://www.raspberrypi.org/documentation/configuration/config-txt/overclocking.md

pjft

@roslof correct. The main thing I seem to get from the explicit v3d overclock is on Saturn and Dreamcast emulation, I believe. The clock frequency does change, at least you can measure it via the command line and it reports the new value.

roslof

@pjft Brilliant. I get to play w/overclock settings again! (yay and boo)

pjft

@roslof to be clear, and it might be just a placebo effect (I posted another thread on that) I'm using the 4k_60 option deliberately to (attempt to?) force the clock to be 10% higher.

Unsure if it actually does anything but thought I'd mention it. I'm on 1080p resolutions and screen.

roslof

@pjft same here with 1080p. I think it's worth my time playing around and testing. I already found undesirable results going slightly above your settings for v3d_freq, so I wager you've already had fun trying to max this thing out.

Darksavior

Since the cpu overclock is gone in mame2015/2016, is there a way to show it? (I was messing with blitter delay, default is 50)

roslof

@Darksavior think I found it.
Enable Cheats in libretro Options, then restart. <--yes, this will enable Overclock CPU in MAME Tab Menu Slider Controls

Tip: To update the overclock value more rapidly, hold Ctrl while moving left or right.

(and what shader are you using? those scanlines look perfect)

Darksavior

@roslof Thanks, that did it. Underclocking seems to help a bit. I'll do more testing later.
I use the crt-pi shader, then I modify it by setting both curvature settings to zero and increasing mask brightness to 1.00, the max.

SeraphisCain

I've been following along with this thread, and underclocking the CPU in MAME definitely helps a lot for several games (though Ibara in particular still has some pretty bad slowdown/audio stuttering). Question though: Is there any way to get MAME to save the CPU underclock setting? Seems like every time I start a game I have to re-set the CPU clock again.

roslof

@SeraphisCain I'm guessing Overclock CPU settings cannot be saved:
https://www.reddit.com/r/MAME/comments/4i0cjp/can_you_save_overclock_cheat_settings/

I know the thread I linked is old, but I haven't been able to find anything to the contrairy.

It kind of blows my mind a little. Things like "Beam Width" for vector games can't be saved either. :|

pjft

Can anyone suggest an optimal/recommended underclock seeing for these games, or will it depends on the game?

A question: what is the underclock actually meant to do? Will it make things slower than they were in the real cab?

Thanks.

AdamBeGood

@SeraphisCain I find Ibara a problem, and Pink Sweets even worse. I'm going to go and play with my settings and see if I can get DeathSmiles better, and maybe Muchi Muchi Pork!

AdamBeGood

@roslof Let us know it you find any overclock settings which really work for you. :)

pjft

@AdamBeGood This might help:

https://www.reddit.com/r/EmulationOnAndroid/comments/cmnxm2/cave_cv1000_games_finally_full_speed_on_android/

I tried DoDonPachi Dai-Fukkatsu 1.5 and... it seemed to indeed be better at 37%? Is this just a tremendous placebo effect? Can someone confirm or tell me how could I confirm this empirically - what to expect, FPS to stay closer to 60fps most times, or is it really just a "feeling" thing?

pjft

@roslof @AdamBeGood @Darksavior @SeraphisCain

Ok, since I'm a sucker for pain and whatnot, I tried to implement/hack away the overclock setting as a core option. I don't even imagine what else this may break, but from my limited testing it seems to work.

I'd appreciate your testing - I may end up submitting it upstream, though I have little hopes of it being approved as I am fairly sure that someone who actually knows the MAME and libretro code architecture would have much better ways of accomplishing it - not to mention that they may also find that this is not something they'd want as a core option.

https://mega.nz/file/FAM3Xa5L#m572GTiMsLOt8cJrjZj0Ay1r1Ds-huEMlox_Z8gMg9g

Very much open to feedback - I tested it briefly on Deathsmiles and DoDonPachi Dai-Fukkatsu and at least the value shown on the slider seems to change accordingly (if you have that menu open, though, you'll need to close it and open again for it to refresh).

If you can test and see if it effectively works as intended, I'd appreciate it. Also, if anyone actually knows the ins and outs of libretro architectures, feel free to say how I should have actually done this right from the get go.

Just extract it to your own /opt/retropie/libretrocores/lr-mame2016 folder, or create a new system (probably a good idea).

If it crashes, just run in verbose and send it my way, but it shouldn't. I just don't know if the default clock for everything is 100%, but from reading the code, it seems to be. That's also what I'm using as a default, but I'm afraid whether it might break games with non-100% default timings, if they exist.

roslof

@pjft brilliant!
I'll devote some time with this today.

Per the post I listed above, I understand that it's possible to set this and have the game fail to boot, but I'd know how to fix this if that happens, I think this is a great option to have.

pjft

@roslof Cool. Just to be clear, as this is a core option, do make sure to create per-game save files before changing it, otherwise any other game you boot with this core will share that same (changed) overclock.

roslof

@pjft understood.
Minor (a non-issue for me): If you mess with the MAME slider option, it will visually lock to whatever value is set. But the slider at the bottom of the screen always matches the core setting. I think this is fine... Impressive that this actually works!

Will continue to verify the core value sticks and that performance is affected, but overall, looking great!

pjft

@roslof Ah, what you're saying is that MAME slider option changes will not reflect in the core options, is that it? Or can you elaborate?

Thanks.

roslof

@pjft sure:

STEPS:

Boot game
Change core setting
TAB/Check slider value for CPU (changes correctly)
Adjust slider value until CPU value changes
Return to core setting (it won't match the slider value)
Change core setting to a new value
TAB/Check slider value for CPU (will not match core; remains visually unchanged)
Observe the actual MAME slider bar at the bottom of the screen. (it WILL match core)

So I believe this is just a visual issue with the TAB/Slider menu not updating if you manually override in MAME. Minor. Would only likely cause confusion to people tuning both Options and TAB/Slider settings simultaneously, which I believe would be low-to-zero folks. #8 above (the bar at the bottom) always seems to be in-sync. So yay!