Accession No

6602


Brief Description

Titan computer slave store, cache memory system, by David Wheeler and Ferranti, English, c. 1963-1973


Origin

Cambridge; England


Maker

University of Cambridge Ferranti


Class

computer technology


Earliest Date

Jan. 1, 1963


Latest Date

Dec. 31, 1973


Inscription Date


Material

Metal (copper, steel?, other); plastic; paper(?) (cardboard)


Dimensions

780mm (height) x 330mm (depth) x 180mm (width)


Special Collection


Provenance

Donated by an individual on or before 09/10/2009.


Inscription


Description Notes

Titan computer slave store, cache memory system, by David Wheeler and Ferranti, English, c. 1963-1973.

One slave store; part of the Titan computer built for University of Cambridge Mathematical Laboratory. Store includes 48 numbered shelves with circuit boards on 42 of them. Connecting wires at the back have been cut loose from other connection. Some cardboard usually fixed to the circuit boards seem loose. Otherwise good condition.

The slave store concept was imagined by David Wheeler (who was responsible for the collaborative efforts of the department and Ferranti in the creation of Titan, a cheaper and less powerful alternative to the Atlas 2 computer also built by Ferranti). The slave store was the first cache memory system, a concept still commonplace in computing.

Condition: good, complete.


References

Mikey McGovern; 'The EDSAC and computing in Cambridge'; Explore Whipple Collections online article; Whipple Museum of the History of Science; University of Cambridge: https://www.whipplemuseum.cam.ac.uk/explore-whipple-collections/calculating-devices/edsac-and-computing-cambridge


Events

Description
Slave stores were created by Professor David Wheeler for the University of Cambridge computer, Titan, in the 1960s. Wheeler’s slave stores are the first instance of a cache memory system, which allow computers to access information at a much higher speed than if it was stored in the main memory store.

The slave store includes 32 fast registers with effectively zero access time. It acts between the core memory store and the processors to hold the most active regions of programs and data, yet work at processor speed. This sped up processes significantly, as memory access is otherwise slower than processing. When the processor attempted to read a word that wasn’t in the slave store, another word would have to be ejected for space to become available for the new word. Additionally, if a word in the slave store had been updated since loading it would have to be rewritten onto the core store before it was discarded.
21/12/2015
Created by: Rosanna Evans on 21/12/2015


FM:47120

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