libretro/beetle-pce-fast-libretro

[Performance Discussion] PCE Accurate is slower than Mednafen PCE

negativeExponent opened this issue · 5 comments

negativeExponent commented

(THIS IS NOT A THIS CORE VS THAT CORE DISCUSSION. THE PURPOSE AT LEAST IS TO OPTIMIZE THE PORT FURTHER IF POSSIBLE)

the libretro_pce core is significantly slower compared to Mednafen PCE.

tested by running the cores in fast-forward mode. im aware this is not the best way to compare as i am bottlenecking my cpu at 100% when running this way but still its slower:

Common setups:

  • everything is on default settings both versions as much as possible
  • both seems to prefer audio enabled when fast-forwarding so lets leave that as is.
  • retroarch uses 16 bit for colors, so i assume the slowdown is not about the color-format
  • using linux-arch with xfce4's window manager disabled for best framerate
  • retroarch uses RGUI with blings disabled (at least the animation stuff)
  • Mednafen has a max fast-forward rate of 15x, but i think i am not at its max limit yet based on screenshot below

libretro PCE:
pce_libretro

Mednafen PCE with frameskip enabled:
pce_mednafen

Mednafen PCE with frameskip disabled:
pce_mednafen_no_frameskip

I cannot do the same comparison with pce_fast or supergrafx since Mednafen is always at max fps with those (about 900fps) and i haven't found yet if mednafen's fast-forward multiplier limit can be changed or set to infinite

Mednafen PCE_Fast with SuperGrafx enabled, frameskip enabled:
pce_fast_supergrafx_mednafen

hizzlekizzle commented

Does mednafen's fast-forward use frameskipping, etc?

negativeExponent commented

ok, found the frameskip option. disabling it, still faster

pce_mednafen_no_frameskip

at 456 fps, its still faster

mrjschulte commented

Is this not part of the inherent price being "paid" for having the more accurate emulation path?

negativeExponent commented

this is a mednafen_pce and libretro_pce comparison, not a pce / pce_fast comparison...