The most commonly used physical types of memory

The most commonly used physical types of memory

Sequential access:

 

·         Memory is organized into units of data, called records. Access must be made in a specific linear sequence

 

Direct access:

 

·         Individual blocks or records have a unique address based on physical location. Access is accomplished by direct access to reach a general vicinity plus sequential searching, counting, or waiting to reach the final location.

 

Random access:

 

·         Each addressable location in memory has a unique, physically wired-in addressing mechanism. The time to access a given location is independent of the sequence of prior accesses and is constant.

 

Spatial locality

 

·         refers to the tendency of execution to involve a number of memory locations that are clustered

 

Temporal locality

 

·         refers to the tendency for a processor to access memory locations that have been used recently

 

__________ memory consists of peripheral storage devices, such as disk and tape.

 

·         External

 

One byte equals __________ bits.

 

·         8

 

From a user's point of view the two most important characteristics of memory are capacity and _____________.

 

·         performance

 

The three performance parameters for memory are: access time, transfer rate, and _________.

 

·         memory cycle time

 

_________ is a random access type of memory that enables one to make a comparison of desired bit locations within a word for a specified match, and to do this for all words simultaneously, thus retrieving a word based on a portion of its contents rather than its address.

 

·         Associative

 

The ________ rate is the rate at which data can be transferred into or out of a memory unit.

 

·         transfer

 

The most commonly used physical types of memory are: semiconductor memory, __________ memory (used for disk and tape), and optical and magneto-optical.

 

·         magnetic surface

 

The three key characteristics of memory are capacity, access time, and _______.

 

·         cost

 

External, nonvolatile memory is referred to as ___________ or auxiliary memory.

 

·         secondary

 

The cache consists of blocks called __________.

 

·         lines

 

__________ computing deals with super computers and their software.

 

·         High-performance

 

The Pentium 4 processor core consists of four major components: fetch/decode unit, out-of-order execution logic, memory subsystem, and __________.

 

·         execution units

 

An interesting feature of the __________ architecture is the use of a small first-in-first-out (FIFO) write buffer to enhance memory write performance.

 

·         ARM

 

__________ memory is a facility that allows programs to address memory from a logical point of view, without regard to the amount of main memory physically available

 

·         Virtual

 

For set-associative mapping the cache control logic interprets a memory address as three fields: Set, Word, and __________.

 

·         Tag