johnb@srchtec.uucp (John Baldwin) (11/27/90)
I am involved with an experimental project involving AI in "firm" real-time. By "firm," I mean that it has few, if any, "hard" deadline items, yet there are significant penalties for repeatedly missing deadlines. This assessment is purely objective. Can anyone point me to some fairly recent references concerning the avoidance of cache hits and/or page faults (swaps) in systems where either instructions or instructions and data are cached?? We have a potential problem with hardware specified by someone other than our organization, and we need to structure our code to optimize its performance given the existing hardware. An approach that was pointed out to me is controlling the gross placement order of object modules by the link editor. In order to know how to do that properly, that is, to minimize cache hits, we need some kind of information concerning the stream of addresses executed or accessed during a "typical" run of the system. Does anyone know how these can be obtained? Our development platforms are DECstations under ULTRIX 4.0, and the target environment is using VxWorks with extensions. I don't have figures for the performance ratios of cache/main memory, or cache reload time. I'll try to get those tomorrow if they will be helpful.
johnb@srchtec.UUCP (John Baldwin) (11/28/90)
Sorry to followup to my own posting, but I simply must correct my own
network faux-pas...
In article <322@srchtec.UUCP> johnb@srchtec.uucp (that's me) writes:
!I am involved with an experimental project involving AI in "firm" real-time.
!By "firm," I mean that it has few, if any, "hard" deadline items, yet there
!are significant penalties for repeatedly missing deadlines. This assessment
!is purely objective.
^^^^^^^^^
I can assure you that my assessment was, in fact, entirely >subjective< !!
Has anyone seen my asbestos suit?
--
John T. Baldwin | "Pereant qui ante nos nostra dixerunt!"
Search Technology, Inc. | (A plague on those who said our good
johnb%srchtec.uucp@mathcs.emory.edu | things before we did!)