Deck 20: Disk Management and I/O Subsystem

Question 1

SSTF algorithm, like SJF___________      of some requests.

A)may cause starvation
B)will cause starvation
C)does not cause starvation
D)causes aging

Answer 1

may cause starvation

Question 2

In the___________  algorithm, the disk arm starts at one end of the disk and moves toward the other end, servicing requests till the other end of the disk. At the other end, the direction is reversed and servicing continues.

A)look
B)scan
C)c-scan
D)c-look

Answer 2

scan

Question 3

In the___________algorithm, the disk head moves from one end to the other, servicing requests along the way. When the head reaches the other end, it immediately returns to the beginning of the disk without servicing any requests on the return trip.

A)look
B)scan
C)c-scan
D)c-look

Answer 3

c-scan

Question 4

The process of dividing a disk into sectors that the disk controller can read and write, before a disk can store data is known as

A)partitioning
B)swap space creation
C)low-level formatting
D)none of the mentioned

Question 5

The data structure for a sector typically contains___________

A)header
B)data area
C)trailer
D)all of the mentioned

Question 6

The header and trailer of a sector contain information used by the disk controller such as___________    and___________    

A)main section & disk identifier
B)error correcting codes (ecc) & sector number
C)sector number & main section
D)disk identifier & sector number

Question 7

The___________program initializes all aspects of the system, from CPU registers to device controllers and the contents of main memory, and then starts the operating system.

A)main
B)bootloader
C)bootstrap
D)rom

Question 8

For most computers, the bootstrap is stored in___________  

A)ram
B)rom
C)cache
D)tertiary storage

Question 9

The scheme used in the above question is known as___________or___________  

A)sector sparing & forwarding
B)forwarding & sector utilization
C)backwarding & forwarding
D)sector utilization & backwarding

Question 10

A disk that has a boot partition is called a

A)start disk
B)end disk
C)boot disk
D)all of the mentioned

Question 11

If one or more devices use a common set of wires to communicate with the computer system, the connection is called___________  

A)cpu
B)monitor
C)wirefull
D)bus

Question 12

When device A has a cable that plugs into device B, and device B has a cable that plugs into device C and device C plugs into a port on the computer, this arrangement is called a

A)port
B)daisy chain
C)bus
D)cable

Question 13

The___________    present a uniform device- access interface to the I/O subsystem, much as system calls provide a standard interface between the application and the operating system.

A)devices
B)buses
C)device drivers
D)i/o systems

Question 14

The___________  register is read by the host to get input.

A)flow in
B)flow out
C)data in
D)data out

Question 15

The___________  register is written by the host to send output.

A)status
B)control
C)data in
D)data out

Question 16

The hardware mechanism that allows a device to notify the CPU is called___________

A)polling
B)interrupt
C)driver
D)controlling

Question 17

The___________    determines the cause of the interrupt, performs the necessary processing and executes a return from the interrupt instruction to return the CPU to the execution state prior to the interrupt.

A)interrupt request line
B)device driver
C)interrupt handler
D)all of the mentioned

Question 18

In general the two interrupt request lines are___________

A)maskable & non maskable interrupts
B)blocked & non maskable interrupts
C)maskable & blocked interrupts
D)none of the mentioned

Question 19

The___________    are reserved for events such as unrecoverable memory errors.

A)non maskable interrupts
B)blocked interrupts
C)maskable interrupts
D)none of the mentioned

Question 20

The___________  can be turned off by the CPU before the execution of critical instruction sequences that must not be interrupted.

A)nonmaskable interrupt
B)blocked interrupt
C)maskable interrupt
D)none of the mentioned

Question 21

The___________      is used by device controllers to request service.

A)nonmaskable interrupt
B)blocked interrupt
C)maskable interrupt
D)none of the mentioned

Question 22

The interrupt vector contains

A)the interrupts
B)the memory addresses of specialized interrupt handlers
C)the identifiers of interrupts
D)the device addresses

Question 23

Division by zero, accessing a protected or non existent memory address, or attempting to execute a privileged instruction from user mode are all categorized as___________  

A)errors
B)exceptions
C)interrupt handlers
D)all of the mentioned

Question 24

For large data transfers,___________    is used.

A)dma
B)programmed i/o
C)controller register
D)none of the mentioned

Question 25

A character stream device transfers

A)bytes one by one
B)block of bytes as a unit
C)with unpredictable response times
D)none of the mentioned