Amithlon speed in WinUAE?

[zevs]

Hi

To my knowledge, Amithlon is supposed to be about twice as fast as WinUAE on the same hardware. This because of no customchips emulation.

So I am woundering could WinUAE have a button for disable custom chips? Would that even have a speed difference?

Does WinUAE emulate custom chips when its set up with Picasso and AHI drivers?

Just woundering

[Toni Wilen]

I have no idea. No one have ever listed any useful speed results = use of exact same hardware and exact same programs. (EDIT: and some real world tests, not some stupid things like sysinfo)

Part of chipset emulation is always running. "Faster RTG" option disables more chipset emulation parts (It could disable more but UAE is an emulator and also see first sentence)

[zevs]

Thanks for the reply, Toni. With modern hardware, speed is not an issue anyway

If only AROS had something close to WinUAE....

[fishyfish]

From my experiences it seems to vary program to program. I seem to recall DoomAttack having slightly higher framerates on Winuae, whereas Quake2 was somewhat faster on Amithlon (using software renderer, obviously Winuae using quarktex/wazp3d is faster than software renderer).

Amithlon "feels" faster, but Id hazzard a guess the only times you'd notice it are in situations where throwing as much raw cpu grunt/ram bandwidth at a problem as possible is important. I could be mistaken, but amithlon also seems to hold up a little better under heavier load.

If I find time I might try a few tests between the 2 on a few different machines (testing both on both hardware setups) sometime over the next week. Possibly Janus UAE on AROS as a third set of tests if I feel inspired enough as well Any suggestions in regards to "useful" tests?

[bernd roesch]

Originally Posted by Toni Wilen

I have no idea. No one have ever listed any useful speed results = use of exact same hardware and exact same programs. (EDIT: and some real world tests, not some stupid things like sysinfo)

Part of chipset emulation is always running. "Faster RTG" option disables more chipset emulation parts (It could disable more but UAE is an emulator and also see first sentence)

bernie told some years ago how amithlon JIT work. the trick is not the simple chipset emulation, the trick is that amithlon JIT Code need not check every CPU branch command if a chipset event happen. this JIT commands need save and restore the CPU Flags for the current amiga JIT code (because the check for chipset event trash the CPu flags for amiga code). and CPU Flag save and restore commands(i did not know how they are named) cost extra cycle on time in modern CPU, because it need sync the CPU (to get all results in order now)

this speedup code with short loops and many branch commands.

Amithlon have a own helper thread for chipset event timing. If this thread notice a chipset event need now process(because time is right) it change the MMU table so the amithlon main thread run into illegal mem accesss exception and the main thread know that now the chipset need emulate.

A simpler chipset did not give lots speedup, because on fast system the chipset code need less time, to exexute