:cycle crunch: /n./ A situation wherein the number of people trying to use a computer simultaneously has reached the point where no one can get enough cycles because they are spread too thin and the system has probably begun to {thrash}. This scenario is an inevitable result of Parkinson's Law applied to timesharing. Usually the only solution is to buy more computer. Happily, this has rapidly become easier since the mid-1980s, so much so that the very term `cycle crunch' now has a faintly archaic flavor; most hackers now use workstations or personal computers as opposed to traditional timesharing systems.
:cycle drought: /n./ A scarcity of cycles. It may be due to a {cycle crunch}, but it could also occur because part of the computer is temporarily not working, leaving fewer cycles to go around. "The {high moby} is {down}, so we're running with only half the usual amount of memory. There will be a cycle drought until it's fixed."
:cycle of reincarnation: /n./ [coined in a paper by T. H. Myer and I.E. Sutherland "On the Design of Display Processors", Comm. ACM, Vol. 11, no. 6, June 1968)] Term used to refer to a well-known effect whereby function in a computing system family is migrated out to special-purpose peripheral hardware for speed, then the peripheral evolves toward more computing power as it does its job, then somebody notices that it is inefficient to support two asymmetrical processors in the architecture and folds the function back into the main CPU, at which point the cycle begins again.
Several iterations of this cycle have been observed in graphics-processor design, and at least one or two in communications and floating-point processors. Also known as `the Wheel of Life', `the Wheel of Samsara', and other variations of the basic Hindu/Buddhist theological idea. See also {blitter}, {bit bang}.
:cycle server: /n./ A powerful machine that exists primarily for running large compute-, disk-, or memory-intensive jobs. Implies that interactive tasks such as editing are done on other machines on the network, such as workstations.
:cypherpunk: /n./ [from {cyberpunk}] Someone interested in the uses of encryption via electronic ciphers for enhancing personal privacy and guarding against tyranny by centralized, authoritarian power structures, especially government. There is an active cypherpunks mailing list at cypherpunks-request@toad.com coordinating work on public-key encryption freeware, privacy, and digital cash. See also {tentacle}.
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:D. C. Power Lab: /n./ The former site of {{SAIL}}. Hackers thought this was very funny because the obvious connection to electrical engineering was nonexistent — the lab was named for a Donald C. Power. Compare {Marginal Hacks}.
:daemon: /day'mn/ or /dee'mn/ /n./ [from the mythological meaning, later rationalized as the acronym `Disk And Execution MONitor'] A program that is not invoked explicitly, but lies dormant waiting for some condition(s) to occur. The idea is that the perpetrator of the condition need not be aware that a daemon is lurking (though often a program will commit an action only because it knows that it will implicitly invoke a daemon). For example, under {{ITS}} writing a file on the {LPT} spooler's directory would invoke the spooling daemon, which would then print the file. The advantage is that programs wanting (in this example) files printed need neither compete for access to nor understand any idiosyncrasies of the {LPT}. They simply enter their implicit requests and let the daemon decide what to do with them. Daemons are usually spawned automatically by the system, and may either live forever or be regenerated at intervals.
Daemon and {demon} are often used interchangeably, but seem to have distinct connotations. The term `daemon' was introduced to computing by {CTSS} people (who pronounced it /dee'mon/) and used it to refer to what ITS called a {dragon}. Although the meaning and the pronunciation have drifted, we think this glossary reflects current (1996) usage.