Which technique allows a computer to run programs larger than its physical RAM by using part of the hard disk as memory?
- A.Caching
- B.Virtual memory
- C.Spooling
- D.Defragmentation
Correct answer
Explanation
The correct answer is B, virtual memory. The operating system reserves an area of the hard disk, called the swap space or the page file, and moves pages a program is not actively using out to it. The program sees one large address space, so software bigger than the installed RAM still runs, though every swap costs time because a disk is far slower than memory.
Option A, caching, does the opposite: it keeps recently used data in a faster memory nearer the processor rather than extending memory onto a slower device. Option C, spooling, queues jobs such as documents waiting to be printed on the disk so the CPU need not wait for a slow peripheral. Option D, defragmentation, rearranges the scattered pieces of files on a disk so they lie in contiguous blocks and read faster; it does not add to memory at all.
Read the full article: Memory and Storage: RAM, ROM, Cache and Units
Practice Questions
View allWhich of the following is the fastest memory in a computer system?
- A.Cache memory
- B.Register
- C.Main memory
- D.Hard disk
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A register is built into the CPU itself and holds the word the arithmetic and logic unit is operating on at that instant, so it is read and written in a single clock cycle.
Read the full explanation →How many bits make one nibble?
- A.2 bits
- B.4 bits
- C.8 bits
- D.16 bits
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A nibble is half a byte, that is four binary digits, and it matters because one nibble is written as exactly one hexadecimal digit, from 0 to F. That is why memory addresses in hexadecimal are read four bits at a time.
Read the full explanation →Which type of memory has to be refreshed thousands of times per second to retain its contents?
- A.SRAM
- B.DRAM
- C.ROM
- D.Flash memory
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Dynamic RAM stores each bit as a charge on a very small capacitor, and that charge leaks away in a few milliseconds, so the memory controller has to read and rewrite every cell continuously.
Read the full explanation →The contents of an EPROM chip are erased by exposing it to
- A.An electrical signal
- B.Ultraviolet light
- C.A magnetic field
- D.Infrared radiation
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An Erasable Programmable Read Only Memory chip carries a small quartz window over the silicon; ultraviolet light shone through that window releases the trapped charge from every cell at once and returns the chip to its blank state, after which it can be programmed again.
Read the full explanation →One terabyte is equal to how many gigabytes?
- A.100 GB
- B.512 GB
- C.1,024 GB
- D.2,048 GB
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Every step in the ladder of storage units multiplies by 1,024, because 1,024 is 2 raised to the power 10 and memory is addressed in binary.
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