I’m getting the feeling a lot of the drivers in FBA (aside from the crowd pullers like Cave/CPS/NeoGeo) are semi-broken. Either that, or there is some very high overhead associated with getting them to run inside FBA. Perhaps synchronization in FBA of the various emulated CPUs takes a heavy hit.
It’s very simple - something like Darius 2 and Ninja Warriors (the Taito games with 3 screens) runs at maybe 20 fps or even lower with FBA on - say - an iPad 2/Mini. With MAME 0.78, it is well above 60fps (I haven’t looked at what it is unthrottled). That is quite the massive difference there.
With CPS1/2 it seems to be that FBA is quite a bit faster though.
Let’s just hope there are not a lot of endian issues inside MAME 0.78 like FBA.