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From: Lawrence D'Oliveiro <ldo@nz.invalid>
Newsgroups: comp.arch
Subject: Re: Address bits again, Article on new mainframe use
Date: Wed, 11 Sep 2024 07:41:36 -0000 (UTC)
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On Wed, 11 Sep 2024 01:53:42 -0000 (UTC), John Levine wrote:

> According to Lawrence D'Oliveiro  <ldo@nz.invalid>:
>>
>>On Mon, 9 Sep 2024 16:55:44 +0000, MitchAlsup1 wrote:
>>
>>> With pages you can swap parts of a segment (page at a time) with
>>> segmentation (only) you cannot swap parts of the segment.
>>
>> Mixing the two seems counterproductive, unless you have few, large
>> segments. Burroughs-style segments were smaller and more numerous than
>> that.
> 
> Multics had paged segments.  The segments were as I recall 18 bit word
> addressed so about a megabyte.  The pages were perhaps 1K.  It worked
> pretty well.

That’s what I mean about “large” segments. I think the segment size 
limited the file size as well.

> An underappreciated advantage of paging is that the pages are all the
> same size.

Nothing underappreciated about it. It’s the reason why we have pages 
nowadays and no segments.