ExecSG was always planned as a fully PPC native Exec replacement.
Thomas Frieden basically took the original Exec which was in 68K ASM and re-implemented it completely in C whilst improving on the original design in the process.
C source-code can obviously be compiled for PPC.
What we are doing now is adding "virtual addressing".
This was not planned originally but the benefits of this are so important that we decided to go ahead and do it.
Benefits include things like less memory fragmentation, faster and more efficient memory allocation and de-allocation, much more robust virtual memory implementation and finally automatic stack enlargement.
Between 30 to 50% of all crashes on the Amiga are due to programs running out of stack-space.
With OS 4, this won't happen anymore as the stack can be automatically enlarged when the system detects a program is about to run out.
