The efficiency of interleaved memory for querying in the database

Аuthors

Brekhov O. M.^*, Tin M. A.^**

Moscow Aviation Institute (National Research University), 4, Volokolamskoe shosse, Moscow, А-80, GSP-3, 125993, Russia

*e-mail: obrekhov@mail.ru
**e-mail: tinmoeaung1985@gmail.com

Abstract

Interleaved memory is a known means to enhance memory performance. Employing this mechanism for data arrays processing when successive numbers of cells of an array are arranged in successive sections of memory cells (per mod m), found application firstly for high-performance computers, and then became widespread in many classes of computing systems.

The above said circumstances have attracted the attention of many researchers to study the efficiency of interleaved memory via analytical modeling and simulation. Query processing in DBs is associated with processing of data sets. As a result, a great number of address calls streams to interleaved memory sections appear. The calls of target treatments of different streams to gain access to the same sections, which will decrease the interleaved memory effeciency.

In this paper, we studied the interleaved memory efficiency by analytical modeling considering address requests of conflicting streams, and obtained the following results. The absolute and relative average and mean-square deviations of a number of sections in use in cycle of memory access as function of interleaved memory sections number, the number of streams of targeted calls and the number of address requests were determined. Number of sections margin of 1.6 will provide at the average 100% request servicing with any number of streams. Relative average number of sections used in one cycle of memory access depends on the number of streams of targeted calls, but does not depend on the number of address requests in a single stream. With increasing number of streams of targeted calls relative average number of sections used in one cycle of memory access tends to a constant 1 — e^—1 = 0.632. Absolute mean-sqaure deviation of the number of sections used in one cycle of memory access decreases with increasing number of targeted calls to flow at a constant absolute value of the average number of sections used. The ratio of the absolute standard deviation to the absolute average number of sections used in one cycle memory access decreases with increasing number of address requests in a stream. The average number of sections used in one cycle of memory access is a significant parameter characterizing the of interleaved memory efficiency.

Keywords:

: memory, efficiency, layer, section, querying, database, streams

References

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