650+ Computer Architecture Solved MCQs

501.

The memory which is used to store the copy of data or instructions stored in larger memories, inside the CPU is called                 

A. level 1 cache
B. level 2 cache
C. registers
D. tlb
Answer» A. level 1 cache
Explanation: these memory devices are generally used to map onto the data stored in the larger memories.
502.

The larger memory placed between the primary cache and the memory is called               

A. level 1 cache
B. level 2 cache
C. eeprom
D. tlb
Answer» B. level 2 cache
Explanation: this is basically used to provide effective memory mapping.
503.

The next level of memory hierarchy after the L2 cache is                 

A. secondary storage
B. tlb
C. main memory
D. register
Answer» D. register
Explanation: none.
504.

The last on the hierarchy scale of memory devices is               

A. main memory
B. secondary memory
C. tlb
D. flash drives
Answer» B. secondary memory
Explanation: the secondary memory is the slowest memory device.
505.

In the memory hierarchy, as the speed of operation increases the memory size also increases.

A. true
B. false
Answer» B. false
Explanation: as the speed of operation increases the cost increases and the size decreases.
506.

If we use the flash drives instead of the harddisks, then the secondary storage can go above primary memory in the hierarchy.

A. true
B. false
Answer» B. false
Explanation: the flash drives will increase the speed of transfer but still it won’t be faster than primary memory.
507.

The reason for the implementation of the cache memory is                   

A. to increase the internal memory of the system
B. the difference in speeds of operation of the processor and memory
C. to reduce the memory access and cycle time
D. all of the mentioned
Answer» B. the difference in speeds of operation of the processor and memory
Explanation: this difference in the speeds of operation of the system caused it to be inefficient.
508.

The effectiveness of the cache memory is based on the property of

A. locality of reference
B. memory localisation
C. memory size
D. none of the mentioned
Answer» A. locality of reference
Explanation: this means that the cache
509.

The temporal aspect of the locality of reference means                   

A. that the recently executed instruction won’t be executed soon
B. that the recently executed instruction is temporarily not referenced
C. that the recently executed instruction will be executed soon again
D. none of the mentioned
Answer» C. that the recently executed instruction will be executed soon again
Explanation: none.
510.

The spatial aspect of the locality of reference means                   

A. that the recently executed instruction is executed again next
B. that the recently executed won’t be executed again
C. that the instruction executed will be executed at a later time
D. that the instruction in close proximity of the instruction executed will be executed in future
Answer» D. that the instruction in close proximity of the instruction executed will be executed in future
Explanation: the spatial aspect of locality of reference tells that the nearby instruction is more likely to be executed in future.
511.

The correspondence between the main memory blocks and those in the cache is given by                     

A. hash function
B. mapping function
C. locale function
D. assign function
Answer» B. mapping function
Explanation: the mapping function is used to map the contents of the memory to the cache.
512.

The algorithm to remove and place new contents into the cache is called

A. replacement algorithm
B. renewal algorithm
C. updation
D. none of the mentioned
Answer» A. replacement algorithm
Explanation: as the cache gets full, older contents of the cache are swapped out with newer contents. this decision is taken by the algorithm.
513.

The write-through procedure is used

A. to write onto the memory directly
B. to write and read from memory simultaneously
C. to write directly on the memory and the cache simultaneously
D. none of the mentioned
Answer» C. to write directly on the memory and the cache simultaneously
Explanation: when write operation is issued then the corresponding operation is performed.
514.

The bit used to signify that the cache location is updated is                   

A. dirty bit
B. update bit
C. reference bit
D. flag bit
Answer» A. dirty bit
Explanation: when the cache location is updated in order to signal to the processor this bit is used.
515.

The copy-back protocol is used

A. to copy the contents of the memory onto the cache
B. to update the contents of the memory from the cache
C. to remove the contents of the cache and push it on to the memory
D. none of the mentioned
Answer» B. to update the contents of the memory from the cache
Explanation: this is another way of performing the write operation, wherein the cache is updated first and then the memory.
516.

The approach where the memory contents are transferred directly to the processor from the memory is called

A. read-later
B. read-through
C. early-start
D. none of the mentioned
Answer» C. early-start
Explanation: none.
517.

In                   protocol the information is directly written into the main memory.

A. write through
B. write back
C. write first
D. none of the mentioned
Answer» A. write through
Explanation: in case of the miss, then the data gets written directly in main memory.
518.

The only draw back of using the early start protocol is                 

A. time delay
B. complexity of circuit
C. latency
D. high miss rate
Answer» B. complexity of circuit
Explanation: in this protocol, the required block is read and directly sent to the processor.
519.

During a write operation if the required block is not present in the cache then               occurs.

A. write latency
B. write hit
C. write delay
D. write miss
Answer» D. write miss
Explanation: this indicates that the
520.

While using the direct mapping technique, in a 16 bit system the higher order 5 bits are used for                   

A. tag
B. block
C. word
D. id
Answer» A. tag
Explanation: the tag is used to identify the block mapped onto one particular cache block.
521.

In direct mapping the presence of the block in memory is checked with the help of block field.

A. true
B. false
Answer» B. false
Explanation: the tag field is used to check the presence of a mem block.
522.

In associative mapping, in a 16 bit system the tag field has               bits.

A. 12
B. 8
C. 9
D. 10
Answer» A. 12
Explanation: the tag field is used as an id for the different memory blocks mapped to the cache.
523.

The associative mapping is costlier than direct mapping.

A. true
B. false
Answer» A. true
Explanation: in associative mapping, all the tags have to be searched to find the block.
524.

The technique of searching for a block by going through all the tags is

A. linear search
B. binary search
C. associative search
D. none of the mentioned
Answer» C. associative search
Explanation: none.
525.

The set-associative map technique is a combination of the direct and associative technique.

A. true
B. false
Answer» A. true
Explanation: the combination of the efficiency of the associative method and the cheapness of the direct mapping, we get the set-associative mapping.
526.

In set-associative technique, the blocks are grouped into               sets.

A. 4
B. 8
C. 12
D. 6
Answer» D. 6
Explanation: the set-associative technique groups the blocks into different sets.
527.

A control bit called                     has to be provided to each block in set- associative.

A. idol bit
B. valid bit
C. reference bit
D. all of the mentioned
Answer» B. valid bit
Explanation: the valid bit is used to indicate that the block holds valid information.
528.

The bit used to indicate whether the block was recently used or not is

A. idol bit
B. control bit
C. reference bit
D. dirty bit
Answer» D. dirty bit
Explanation: the dirty bit is used to show that the block was recently modified and for a replacement algorithm.
529.

Data which is not up-to date is called as                 

A. spoilt data
B. stale data
C. dirty data
D. none of the mentioned
Answer» B. stale data
Explanation: none.
530.

The main memory is structured into modules each with its own address register called               

A. abr
B. tlb
C. pc
D. ir
Answer» A. abr
Explanation: abr stands for address buffer register.
531.

When consecutive memory locations are accessed only one module is accessed at a time.

A. true
B. false
Answer» A. true
Explanation: in a modular approach to memory structuring only one module can be accessed at a time.
532.

In memory interleaving, the lower order bits of the address is used to

A. get the data
B. get the address of the module
C. get the address of the data within the module
D. none of the mentioned
Answer» B. get the address of the module
Explanation: to implement parallelism in data access we use interleaving.
533.

The number successful accesses to memory stated as a fraction is called as

A. hit rate
B. miss rate
C. success rate
D. access rate
Answer» A. hit rate
Explanation: the hit rate is an important factor in performance measurement.
534.

The number failed attempts to access memory, stated in the form of a fraction is called as                     

A. hit rate
B. miss rate
C. failure rate
D. delay rate
Answer» B. miss rate
Explanation: the miss rate is a key factor in deciding the type of replacement algorithm.
535.

In associative mapping during LRU, the counter of the new block is set to ‘0’ and all the others are incremented by one, when            occurs.

A. delay
B. miss
C. hit
D. delayed hit
Answer» B. miss
Explanation: miss usually occurs when the memory block required is not present in the cache.
536.

In LRU, the referenced blocks counter is set to’0′ and that of the previous blocks are incremented by one and others remain same, in the case of

A. hit
B. miss
C. delay
D. none of the mentioned
Answer» A. hit
Explanation: if the referenced block is present in the memory it is called as hit.
537.

If hit rates are well below 0.9, then they’re called as speedy computers.

A. true
B. false
Answer» B. false
Explanation: it has to be above 0.9 for speedy computers.
538.

The extra time needed to bring the data into memory in case of a miss is called as                       

A. delay
B. propagation time
C. miss penalty
D. none of the mentioned
Answer» C. miss penalty
Explanation: none.
539.

The miss penalty can be reduced by improving the mechanisms for data transfer between the different levels of hierarchy.

A. true
B. false
Answer» A. true
Explanation: the extra time needed to bring the data into memory in case of a miss is called as miss penalty.
540.

The CPU is also called as                   

A. processor hub
B. isp
C. controller
D. all of the mentioned
Answer» B. isp
Explanation: isp stands for instruction set processor.
541.

A common strategy for performance is making various functional units operate parallelly.

A. true
B. false
Answer» A. true
Explanation: by parallelly accessing data we can have a pipelined processor.
542.

The PC gets incremented

A. after the instruction decoding
B. after the ir instruction gets executed
C. after the fetch cycle
D. none of the mentioned
Answer» C. after the fetch cycle
Explanation: the pc always points to the next instruction to be executed.
543.

Which register in the processor is single directional?

A. mar
B. mdr
C. pc
D. temp
Answer» A. mar
Explanation: the mar is single directional as it just takes the address from the processor bus and passes it to the external bus.
544.

The transparent register/s is/are

A. y
B. z
C. temp
D. all of the mentioned
Answer» D. all of the mentioned
Explanation: these registers are usually used to store temporary values.
545.

Which register is connected to the MUX?

A. y
B. z
C. r0
D. temp
Answer» A. y
Explanation: the mux can either read the operand from the y register or increment the pc.
546.

The registers, ALU and the interconnecting path together are called as               

A. control path
B. flow path
C. data path
D. none of the mentioned
Answer» C. data path
Explanation: none.
547.

The input and output of the registers are governed by                       

A. transistors
B. diodes
C. gates
D. switches
Answer» D. switches
Explanation: none.
548.

When two or more clock cycles are used to complete data transfer it is called as                   

A. single phase clocking
B. multi-phase clocking
C. edge triggered clocking
D. none of the mentioned
Answer» B. multi-phase clocking
Explanation: this is basically used in systems without edge-triggered flip flops.
549.

                  signal is used to show complete of memory operation.

A. mfc
B. wmfc
C. cfc
D. none of the mentioned
Answer» A. mfc
Explanation: mfc stands for memory function complete.
550.

                    signal enables the processor to wait for the memory operation to complete.

A. mfc
B. tlb
C. wmfc
D. alb
Answer» C. wmfc
Explanation: this signal stands for wait for memory function complete.
551.

The small extremely fast, RAM’s all called as                   

A. cache
B. heaps
C. accumulators
D. stacks
Answer» B. heaps
Explanation: cache’s are extremely essential in single bus organisation to achieve fast operation.
552.

To extend the connectivity of the processor bus we use               

A. pci bus
B. scsi bus
C. controllers
D. multiple bus
Answer» A. pci bus
Explanation: the pci bus basically is used to connect to memory devices.
553.

The bus used to connect the monitor to the CPU is                           

A. pci bus
B. scsi bus
C. memory bus
D. rambus
Answer» B. scsi bus
Explanation: the scsi (small component system interconnect) is used to connect to display devices.
554.

ANSI stands for                             

A. american national standards institute
B. american national standard interface
C. american network standard interfacing
D. american network security interrupt
Answer» A. american national standards institute
Explanation: it is one of the standards of developing a bus.
555.

The general purpose registers are combined into a block called as               

A. register bank
B. register case
C. register file
D. none of the mentioned
Answer» C. register file
Explanation: to make the access of the
556.

In               technology, the implementation of the register file is by using an array of memory locations.

A. vlsi
B. ansi
C. isa
D. asci
Answer» A. vlsi
Explanation: by doing so the access of the registers can be made faster.
557.

In a three BUS architecture, how many input and output ports are there?

A. 2 output and 2 input
B. 1 output and 2 input
C. 2 output and 1 input
D. 1 output and 1 input
Answer» C. 2 output and 1 input
Explanation: that is enabling reading from two locations and writing into one.
558.

CISC stands for                     

A. complete instruction sequential compilation
B. computer integrated sequential compiler
C. complex instruction set computer
D. complex instruction sequential compilation
Answer» C. complex instruction set computer
Explanation: the cisc machines are well adept at handling multiple bus organisation.
559.

There exists a separate block consisting of various units to decode an instruction.

A. true
B. false
Answer» A. true
Explanation: this block is used to decode the instruction and place it in the ir.
560.

There exists a separate block to increment the PC in multiple BUS organisation.

A. true
B. false
Answer» A. true
Explanation: none.
561.

                  are the different type/s of generating control signals.

A. micro-programmed
B. hardwired
C. micro-instruction
D. both micro-programmed and hardwired
Answer» D. both micro-programmed and hardwired
Explanation: the above is used to generate control signals in different types of system architectures.
562.

The type of control signal is generated based on                   

A. contents of the step counter
B. contents of ir
C. contents of condition flags
D. all of the mentioned
Answer» D. all of the mentioned
Explanation: based on the information above the type of control signal is decided.
563.

What does the hardwired control generator consist of?

A. decoder/encoder
B. condition codes
C. control step counter
D. all of the mentioned
Answer» D. all of the mentioned
Explanation: the cu uses the above blocks and ir to produce the necessary signal.
564.

What does the end instruction do?

A. it ends the generation of a signal
B. it ends the complete generation process
C. it starts a new instruction fetch cycle and resets the counter
D. it is used to shift the control to the processor
Answer» C. it starts a new instruction fetch cycle and resets the counter
Explanation: it is basically used to start the generation of a new signal.
565.

BR…

A. true
B. false
Answer» A. true
Explanation: the signal is generated using the logic of the formula above.
566.

The name hardwired came because the sequence of operations carried out is determined by the wiring.

A. true
B. false
Answer» A. true
Explanation: in other words hardwired is another name for hardware control signal generator.
567.

The benefit of using this approach is

A. it is cost effective
B. it is highly efficient
C. it is very reliable
D. it increases the speed of operation
Answer» D. it increases the speed of operation
Explanation: none.
568.

The disadvantage/s of the hardwired approach is                   

A. it is less flexible
B. it cannot be used for complex instructions
C. it is costly
D. less flexible & cannot be used for complex instructions
Answer» D. less flexible & cannot be used for complex instructions
Explanation: the more complex the instruction set less applicable to a hardwired approach.
569.

In micro-programmed approach, the signals are generated by               

A. machine instructions
B. system programs
C. utility tools
D. none of the mentioned
Answer» A. machine instructions
Explanation: the machine instructions generate the signals.
570.

A word whose individual bits represent a control signal is               

A. command word
B. control word
C. co-ordination word
D. generation word
Answer» B. control word
Explanation: the control word is used to get the different types of control signals required.
571.

A sequence of control words corresponding to a control sequence is called                 

A. micro routine
B. micro function
C. micro procedure
D. none of the mentioned
Answer» A. micro routine
Explanation: the micro routines are used to perform a particular task.
572.

Individual control words of the micro routine are called as               

A. micro task
B. micro operation
C. micro instruction
D. micro command
Answer» C. micro instruction
Explanation: the each instruction which put together performs the task.
573.

The special memory used to store the micro routines of a computer is

A. control table
B. control store
C. control mart
D. control shop
Answer» B. control store
Explanation: the control store is used as a reference to get the required control routine.
574.

Every time a new instruction is loaded into IR the output of                   is loaded into UPC.

A. starting address generator
B. loader
C. linker
D. clock
Answer» A. starting address generator
Explanation: the starting address generator is used to load the address of the next micro instruction.
575.

The case/s where micro-programmed can perform well                                 

A. when it requires to check the condition codes
B. when it has to choose between the two alternatives
C. when it is triggered by an interrupt
D. none of the mentioned
Answer» D. none of the mentioned
Explanation: none.
576.

The signals are grouped such that mutually exclusive signals are put together.

A. true
B. false
Answer» A. true
Explanation: this is done to improve the efficiency of the controller.
577.

Highly encoded schemes that use compact codes to specify a small number of functions in each micro instruction is                   

A. horizontal organisation
B. vertical organisation
C. diagonal organisation
D. none of the mentioned
Answer» B. vertical organisation
Explanation: none.
578.

The directly mapped cache no replacement algorithm is required.

A. true
B. false
Answer» A. true
Explanation: the position of each block is pre-determined in the direct mapped cache, hence no need for replacement.
579.

In associative mapping during LRU, the counter of the new block is set to ‘0’ and all the others are incremented by one when            occurs.

A. delay
B. miss
C. hit
D. delayed hit
Answer» B. miss
Explanation: miss usually occurs when the memory block required is not present in the cache.
580.

In set associative and associative mapping there exists less flexibility.

A. true
B. false
Answer» B. false
Explanation: the above two methods of mapping the decision of which block to be removed rests with the cache controller.
581.

The algorithm which replaces the block which has not been referenced for a while is called            

A. lru
B. orf
C. direct
D. both lru and orf
Answer» A. lru
Explanation: lru stands for least recently used first.
582.

The algorithm which removes the recently used page first is                   

A. lru
B. mru
C. ofm
D. none of the mentioned
Answer» B. mru
Explanation: in mru it is assumed that the page accessed now is less likely to be accessed again.
583.

The LRU can be improved by providing a little randomness in the access.

A. true
B. false
Answer» A. true
Explanation: none.
584.

The counter that keeps track of how many times a block is most likely used is

A. count
B. reference counter
C. use counter
D. probable counter
Answer» B. reference counter
Explanation: none.
585.

The key factor/s in commercial success of a computer is/are                   

A. performance
B. cost
C. speed
D. both performance and cost
Answer» D. both performance and cost
Explanation: the performance and cost of the computer system is a key decider in the commercial success of the system.
586.

A common measure of performance is

A. price/performance ratio
B. performance/price ratio
C. operation/price ratio
D. none of the mentioned
Answer» A. price/performance ratio
Explanation: if this measure is less than one then the system is optimal.
587.

The performance depends on

A. the speed of execution only
B. the speed of fetch and execution
C. the speed of fetch only
D. the hardware of the system only
Answer» B. the speed of fetch and execution
Explanation: the performance of a system is decided by how quick an instruction is brought into the system and executed.
588.

The main purpose of having memory hierarchy is to                   

A. reduce access time
B. provide large capacity
C. reduce propagation time
D. reduce access time & provide large capacity
Answer» D. reduce access time & provide large capacity
Explanation: by using the memory hierarchy, we can increase the performance of the system.
589.

The memory transfers between two variable speed devices are always done at the speed of the faster device.

A. true
B. false
Answer» A. true
Explanation: none.
590.

An effective to introduce parallelism in memory access is by                 

A. memory interleaving
B. tlb
C. pages
D. frames
Answer» A. memory interleaving
Explanation: interleaving divides the memory into modules.
591.

The performance of the system is greatly influenced by increasing the level 1 cache.

A. true
B. false
Answer» A. true
Explanation: this is so because the l1 cache is onboard the processor.
592.

Two processors A and B have clock frequencies of 700 Mhz and 900 Mhz respectively. Suppose A can execute an instruction with an average of 3 steps and B can execute with an average of 5 steps. For the execution of the same instruction which processor is faster.

A. a
B. b
C. both take the same time
D. insufficient information
Answer» A. a
Explanation: none.
593.

If the instruction Add R1, R2, R3 is executed in a system which is pipelined, then the value of S is (Where S is a term of the Basic performance equation).

A. 3
B. ~2
C. ~1
D. 6
Answer» C. ~1
Explanation: pipelining is a process of fetching an instruction during the execution of other instruction.
594.

The physical memory is not as large as the address space spanned by the processor.

A. true
B. false
Answer» A. true
Explanation: this is one of the main reasons for the usage of virtual memories.
595.

The program is divided into operable parts called as                     

A. frames
B. segments
C. pages
D. sheets
Answer» B. segments
Explanation: the program is divided into parts called as segments for ease of execution.
596.

The techniques which move the program blocks to or from the physical memory is called as               

A. paging
B. virtual memory organisation
C. overlays
D. framing
Answer» B. virtual memory organisation
Explanation: by using this technique the program execution is accomplished with a usage of less space.
597.

The binary address issued to data or instructions are called as               

A. physical address
B. location
C. relocatable address
D. logical address
Answer» D. logical address
Explanation: the logical address is the random address generated by the processor.
598.

                      is used to implement virtual memory organisation.

A. page table
B. frame table
C. mmu
D. none of the mentioned
Answer» C. mmu
Explanation: the mmu stands for memory management unit.
599.

              translates the logical address into a physical address.

A. mmu
B. translator
C. compiler
D. linker
Answer» A. mmu
Explanation: the mmu translates the logical address into a physical address by adding an offset.
600.

The DMA doesn’t make use of the MMU for bulk data transfers.

A. true
B. false
Answer» B. false
Explanation: the dma stands for direct memory access, in which a block of data gets directly transferred from the memory.
Tags
  • Question and answers in Computer Architecture,
  • Computer Architecture multiple choice questions and answers,
  • Computer Architecture Important MCQs,
  • Solved MCQs for Computer Architecture,
  • Computer Architecture MCQs with answers PDF download