Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!zaphod.mps.ohio-state.edu!sdd.hp.com!spool.mu.edu!snorkelwacker.mit.edu!primerd!tiger1!efeustel From: efeustel@prime.com (Ed Feustel) Newsgroups: comp.arch Subject: Re: Segmented Architectures ( formerly Re: 48-bit computers) Message-ID: Date: 1 Apr 91 16:24:08 GMT Article-I.D.: tiger1.efeustel.670523048 References: <1991Mar27.172325.10800@sj.nec.com> <00670208556@elgamy.RAIDERNET.COM> <1655@spim.mips.COM> Lines: 11 Nntp-Posting-Host: tiger1 One of the better uses for segments is when the segment is variable size. The size is tailored to the object that is represented by the segment. If each segment has its own page table, then the segment can grow or contract independent of all other segments as was suggested in a previous article on the subject. One should not be forced to have a segment which is 2**y bytes long. One should have a segment that is n-bytes where n is the size of the object. One can compromise this to have segment sizes which are multiples of words or pages in order to improve performance. A stack can use this feature in that a segment fault for length should result when one attempts to step off the segment.