gnu@hoptoad.uucp (John Gilmore) (01/29/86)
The press releases make much of the 40 bit virtual addresses.
Does anyone have technical info on what, if any, good it is to have
a 40 bit virtual address in a 32 bit machine? I presume they tack
on a "segment" prefix of some sort to your 32 bit address value,
but this is supposition from hints in the press release.
--
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# John Gilmore {sun,ptsfa,lll-crg,nsc}!hoptoad!gnu jgilmore@lll-crg.arpajohnl@ima.UUCP (01/31/86)
See my article in net.micro.pc on the RT PC for a discussion of how the RT's segmentation works. In short, the system can have up to 4K segments, each logically up to 2^28 bytes long, and 16 segments at a time can be mapped into your address space. The win is that all 4K segments are defined to the address mapping hardware, so that mapping a segment into your address space is very cheap. I'd be happy to answer questions if I can. John Levine