??>TH: Okay. But, why would he want to read the who thing? Setting up
??>TH: some indexes would be simpler and less overhead.
ML>Maybe even disk access isn't fast enough assumimg cache
ML>sizes are even respectably limited!
???
Why does it have to be so fast in the first place?
ML>Consider the problem of having a ten position Field Day contest
ML>operation where-in all ten positions have to have access to not
ML>only the NodeList, but some 1,750,000 records in yet a bigger
ML>list.
ML>The object is to instantly, in less than one second, recover all
ML>the data associated with two records, the one you are attempting
ML>to contact in the contest, and the closest FidoNet SysOp,
ML>geographicly, to that place. The difference between you getting
ML>the station you decide to call and someone else is often measured
ML>in quarters of a second in real-time. Thus ALL the information, as
ML>to previous contacts, needed contacts, related sites for FidoNet
ML>drop-off of the emergency 'message' that is produced by the
ML>contact; all must be done in real-time.
Indexes and cross-indexing will accomplish this, and probably in less
time than that. Sure, direct RAM access will be faster, but at the
expence of eating up a lot of systems resources, ie. RAM. If the
operating system runs out of RAM, then it has to swap out to disk,
and then you will loose all that gain and more.
Listen, accessing ten chained records in a 10-Meg (or 100-Meg) file
in under a second is no trick using random access.
ML>Worse, it has to be done for up to as many as at 23 different
ML>workstations on the LAN, perhaps all in the same exact second!
Expect a short wait. [grin]
ML>Until you've done this job and tried it all, you really don't know
ML>what is really needed in network response times, either, friend..
I was a systems administrater programming this sort of thing for ten
years, my friend. Try it in FORTRAN and assembly for a real hoot. [grin]
Anyway, enjoyed the discussion, but I have get some serious studying
down. cya l8ter...
ML>On thread.. on topic; what a delightful memorable experience in C++..
ML>:)
What da ya think of them *Brooklin* Dodgers? [grin]
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