Emulator vs simulator performance

[David Hayden]

Interesting. So the 60x slowdown claim appears fairly accurate. Decimal free42 is about 49 times faster than emu42.

Eric Smith can probably speak more knowledgeably than I can, but here are some thoughts.

The Saturn CPU is a pretty different from an x86. Emulating it might be harder than a more traditional one. Things like register fields might be hard. And if the Saturn BCD arithmetic doesn't translate well to x86 then that could be a problem.

Also, it's my understanding that the 42s is implemented in SysRPL. That adds another layer of complication and slowdown compared to assembly language. As I recall working with C on a 50g, the speed difference there is something like native C code is about 5x faster than Saturn assembly, which is about 5x faster than SysRPL, which is about 5x faster than User RPL. Those values may vary somewhat, but I do recall specifically that C code is about 100x faster than userRPL on the 50g.

Dave