Yeah, I know. There was actually a discussion about this on the list a month or so ago. The problem is that calling any flavour of the sleep() system call incurs a fairly large time overhead, so that when it's called, there almost certainly won't be time to do the emulation work for the frame when before it needs to be displayed -- hence the skipping. The Barath frameskipper handles this in a fairly intelligent way and minimizes the impact; the DOS frameskipper does not. Not surprising since who cares if your game is pegging your CPU if you're running DOS?
On Tue, Feb 18, 2003 at 10:09:13AM -0500, Caleb Shay wrote: > Sure enough, disabling sleepidle makes the dos frameskipper work fine. > So, the next questions is, what's wrong with sleep idle? I thought it > was just supposed to keep your cpu from being maxed when the emulator > isn't actually doing anything, not actually slow down emulation. > > Caleb > > On Tue, 2003-02-18 at 09:55, Steve Freeland wrote: > > This only makes sense (to me anyways) if you have the > > sleepidle option enabled. Is this the case? Otherwise, there really > > shouldn't be much performance difference between the frameskippers if > > the game is at all able to run at full speed (ie, with -noth) > > > > On Mon, Feb 17, 2003 at 08:43:43AM -0500, Caleb Shay wrote: > > > Well, that sucks. Since, with my CPU running 99% idle, the DOS > > > frameskip code renders pretty much everything unplayable. > > > > > > Example: > > > > > > With my machine 99+% idle (according to top) > > > > > > xmame.x11 -noth ssf2 -> Gives me an average of 140 fps > > > xmame.x11 -fsr 1 ssf2 -> No skipped frames, locked at 60fps > > > xmame.x11 -fsr 0 ssf2 -> Constantly auto-skipping 8 frames and a frame > > > rate of 18fps > > > > > > > > > Caleb > > > > -- > /*--------------------------------------------------------------------- > Caleb Shay "UNIX _IS_ user friendly. > Programmer/System Administrator It's just particular about > Providence, RI who its friends are." > ---------------------------------------------------------------------*/ > > > _______________________________________________ > Xmame mailing list > [EMAIL PROTECTED] > http://toybox.twisted.org.uk/mailman/listinfo/xmame -- | One would think the grandeur of the universe needs | no help from Walter Cronkite. One would think Steve Freeland | wrong. -- Neil Postman, "Amusing Ourselves To Death" _______________________________________________ Xmame mailing list [EMAIL PROTECTED] http://toybox.twisted.org.uk/mailman/listinfo/xmame
