Re: why the 16meg space size limit? -- MI400

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====> a system pointer to a usrspc (actually to any) object is constructed like this (each character=4-bits):

KAAAA000 00000000 SSSSSSSS SS00TTAA

Roughly K is the type of the pointer, the As are authority bits, the 0s are zeroes, the Ss are a 'segment'

address, and the Ts are the object type. The object starts at address SSSSSSSSSS000000. Note, that

the low-order 24 bits are zero. When you create a spacepointer from the system pointer, these low-order

24 bits contains an offset within the space, hence the 26Mb limitation.

So, could a teraspace pointer have a diff "k" value and shift the segment value over a byte or two?

KAAAA000 0000SSSS SSSSSS00 0000TTAA

Then use the addr xlate tables or whatever built into the cpu to provide a contiguous looking group of segments? The intel 386 architecture solved the segment problem with paging and addr xlate support built into the cpu. no? I am not sure.

Steve

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