moby


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moby

(jargon)
/moh'bee/ (From MIT, seems to have been in use among model railroad fans years ago. Derived from Melville's "Moby Dick", some say from "Moby Pickle") 1. Large, immense, complex, impressive. "A Saturn V rocket is a truly moby frob." "Some MIT undergrads pulled off a moby hack at the Harvard-Yale game."

2. (Obsolete) The maximum address space of a computer (see below). For a 680[234]0 or VAX or most modern 32-bit architectures, it is 4,294,967,296 8-bit bytes (four gigabytes).

3. A title of address (never of third-person reference), usually used to show admiration, respect, and/or friendliness to a competent hacker. "Greetings, moby Dave. How's that address-book thing for the Mac going?"

4. In backgammon, doubles on the dice, as in "moby sixes", "moby ones", etc. Compare this with bignum: double sixes are both bignums and moby sixes, but moby ones are not bignums (the use of "moby" to describe double ones is sarcastic).

5. The largest available unit of something which is available in discrete increments. Thus a "moby Coke" is not just large, it's the largest size on sale.

This term entered hackerdom with the Fabritek 256K memory added to the MIT AI PDP-6 machine, which was considered unimaginably huge when it was installed in the 1960s (at a time when a more typical memory size for a time-sharing system was 72 kilobytes). Thus, a moby is classically 256K 36-bit words, the size of a PDP-6 or PDP-10 moby. Back when address registers were narrow the term was more generally useful, because when a computer had virtual memory mapping, it might actually have more physical memory attached to it than any one program could access directly. One could then say "This computer has six mobies" meaning that the ratio of physical memory to address space is six, without having to say specifically how much memory there actually is. That in turn implied that the computer could timeshare six "full-sized" programs without having to swap programs between memory and disk.

Nowadays the low cost of processor logic means that address spaces are usually larger than the most physical memory you can cram onto a machine, so most systems have much *less* than one theoretical "native" moby of core. Also, more modern memory-management techniques (especially paging) make the "moby count" less significant. However, there is one series of widely-used chips for which the term could stand to be revived --- the Intel 8088 and 80286 with their incredibly brain-damaged segmented-memory designs. On these, a "moby" would be the 1-megabyte address span of a segment/offset pair (by coincidence, a PDP-10 moby was exactly one megabyte of nine-bit bytes).
References in periodicals archive ?
The Moby & Tate knit collection features luxurious threads and playful embellishments creating the perfect combination of fun and fashion.
Moby would go on to work with such well-established rock'n'roll icons as David Bowie, Erasure, Pet Shop Boys and Michael Jackson, whether collaborating with them directly or remixing their older work.
Sasha was lying motionless, comatose on the rocks, and Moby limped his way towards the sea.
Sasha was laying motionless comatose on the rocks, and Moby limped his way towards the sea.
In 1999 and 2000, Moby found pop success with the album Play, which produced many hit singles, including the excellent Porcelain.
As with previous Moby albums, 'Last Night' features many guest vocalists, although don't expect to recognise any of them.
Moby has never talked about the financial rewards for such heavy licensing, but it's safe to assume, especially considering the brands who used his songs, that they were plentiful.
Moby said: "I'm a big Blondie fan but I'm also a fan of Debbie and everything the band stood for.
Moby may champion soothing sounds, but his outspoken politics continue to rankle many pundits.
musician Moby on the Recording Industry Association of America's lawsuits against file traders, posted to Moby.
You will find Ahab, for example, the captain of the Pequod, setting out on his voyage to seek vengeance on Moby Dick, the white whale who has grievously wounded Ahab during their last encounter, for Ahab believes that the white whale willfully and maliciously inflicted the wound that Ahab bears.