Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!wuarchive!zaphod.mps.ohio-state.edu!unix.cis.pitt.edu!pitt!vax.cs.pitt.edu!jonathan From: jonathan@cs.pitt.edu (Jonathan Eunice) Newsgroups: comp.arch Subject: memory management implementations Message-ID: Date: 2 Apr 91 02:37:14 GMT Sender: news@pitt.UUCP Organization: University of Pittsburgh Computer Science Lines: 11 My impression is that most workstations, and perhaps a fair number of other systems as well, use some low-cost approximation of the LRU algorithm--such as a variation on the Clock algorithm--for page replacement. (If this is wrong, let me know.) Are the LRU approximations used "good enough?" That is, with all of the transistors we can now put on a chip or multi-chip CPU, does it make sense to use more expensive, closer-to-true-LRU algorithms? Would this help VM performance some measurable amount, and is it reasonable to do? What is the real-estate/transistor-count cost? What is the design/opportunity costs?