What makes the Prime so fast?

[David Hayden]

(02-22-2016 10:57 PM)David Wrote:  I would have preferred that the HP Prime evolved from the HP48/49/50 OS

In addition to the CPU speed, another big reason that the Prime is fast is because it isn't based on the 48/49/50 OS. SysRPL is slower than machine code. User RPL is slower than SysRPL. By way of comparison, C code running on the 50G is typically about 100 times faster than UserRPL in my experience. I haven't compared it to SysRPL, but I suspect it's about 5 times faster. Much of the 48/49/50 OS is written in SysRPL.

Now it's true that Prime programs run as an interpreted byte code, but I suspect that code doesn't have to do all the parameter checking that UserRPL does.

Lastly, the memory management in the RPL calcs makes updating the OS really difficult. Garbage collection can happen at pretty much any time, which means that all of the data can move.