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MCL 2.0.1 ptable init problem on LC/Performa 475

High MCLers,
we have received MCL 2.0.1 now. Whereas we generally haven't encountered
running it [on either Quadara 950 or LC/Performa 475 platforms using System 7.1]. The ptable init prevents the Finder to start on our LC/Performa 475 platforms [but
doesn't cause any trouble on the Quadra 950]. The MCL FAQ states that the ptable init is very vulnerable to minor changes when a new Macintosh model or operating
system is released. 

Therefore, I would appreciate assistance on the following questions:

1. Are there any known problems for the ptable init and the 68LC040 processor?

2. Are there any known incompatibilities between the ptable init and other inits?

3. The ptable init is intended to make the ephemeral garbage collection more
   efficient. On the other hand, from the MCL documentation [MCL reference,
   page 633 and MCL FAQ] it is not quite clear for me under which circumstances      the ptable init really provides performance gains. 
   MCL Reference p633: 
   The MCL Kernel can provide MMU support to the ephemeral garbage collector in      the following circumstances:
   - ...
   - ...
   - When the MMU is configured to use a reasonably small page size (8k or 4k).
     Currrently this means *either* a 68040 processor, the use of System 7 virtual
     memory, *or* the use of the ptable system extension provided as part of 
     the MCL distribution. [Questions: Does this mean I don't win anything
     when using the ptable extension on a 68040 processor? Are the 68LC040
     and the 68040 equivalent with respect to that? Does using virtual memory
     make the ptable init obsolete?]
   ...., but you will have to decide whether or not the benefit of improved EGC      performance is worth the cost, depending on your exact usage of MCL and your      MAC. [Question: Can someone tell me criteria to base that decision on?]
   You should probably use init only if all of the following are true:
   - Your Macintosh's CPU is an 040, ... [Question: This seems to contradict 
     the MCL Reference. Can anyone enlighten me?]

Thanks for your assistance.

Kind regards, Frank Plassmeier