[Mono-list] FAQ additions - resubmitted v2.0

Miguel de Icaza miguel@ximian.com
10 Jul 2001 19:00:15 -0400


> 6. What level of performance can be expected? What if Mono can't achieve 
> that level of performance?

Q: How fast will be Mono?

A: We can not predict the future, but a conservative estimate is that
   it would be at least `as fast as other JIT engines'.

   Now, wishfully thinking I hope that we will ship various JITs with
   Mono just like Microsoft has done.  A fast JITer when maximum
   performance is not needed, but fast load times are important;  And
   an optimizing JITer that would be slower at generating code but
   produce more optimal output.

   The CIL has some advantages over the Java byte code:  it is really
   an intermediate representation and there are a number of
   restrictions on how you can emit CIL code that simplify creating
   better JIT engines.

   For example, on the CIL the stack is not really an abstraction
   available for the code generator to use at will: it is just a way
   of creating a postfix representation of the parsed tree.  At any
   given call point or return point, the contents of the stack are
   expected to contain the same object types independently of how the
   instructions was reached.