Operating System Multiple Choice Questions on “RAID Structure”.
1. RAID level 3 supports a lower number of I/Os per second, because _______________
a) Every disk has to participate in every I/O request
b) Only one disk participates per I/O request
c) I/O cycle consumes a lot of CPU time
d) All of the mentioned
Answer: a
Clarification: None.
2. RAID level _____ is also known as block interleaved parity organisation and uses block level striping and keeps a parity block on a separate disk.
a) 1
b) 2
c) 3
d) 4
Answer: d
Clarification: None.
3. A performance problem with _________ is the expense of computing and writing parity.
a) non-parity based RAID levels
b) parity based RAID levels
c) all RAID levels
d) none of the mentioned
Answer: b
Clarification: None.
4. In RAID level 4, one block read, accesses __________
a) only one disk
b) all disks simultaneously
c) all disks sequentially
d) none of the mentioned
Answer: a
Clarification: Other requests are allowed to be processed by other disks.
5. The overall I/O rate in RAID level 4 is ____________
a) low
b) very low
c) high
d) none of the mentioned
Answer: c
Clarification: All disks can be read in parallel.
6. A write of a block has to access ____________
a) the disk on which the block is stored
b) parity disk
c) a parity block
d) all of the mentioned
Answer: d
Clarification: None.
7. RAID level 5 is also known as ____________
a) bit-interleaved parity organization
b) block-interleaved parity organization
c) block-interleaved distributed parity
d) memory-style ECC organization
Answer: c
Clarification: None.
8. RAID level ____ spreads parity and data among all N+1 disks rather than storing data in N disks and parity in 1.
a) 3
b) 4
c) 5
d) 6
Answer: c
Clarification: None.
9. The potential overuse of a single parity disk is avoided in RAID level _______
a) 3
b) 4
c) 5
d) all of the mentioned
Answer: c
Clarification: None.
10. RAID level 0+1 is used because, RAID level 0 provides ______ whereas RAID level 1 provides ________
a) performance, redundancy
b) performance, reliability
c) redundancy, performance
d) none of the mentioned
Answer: b
Clarification: None.
11. If a disk fails in RAID level ___________ rebuilding lost data is easiest.
a) 1
b) 2
c) 3
d) 4
Answer: a
Clarification: Data can be copied from another disk in raid level 1, for other raid levels all other disks have to be accessed.
12. Where performance and reliability are both important, RAID level ____ is used.
a) 0
b) 1
c) 2
d) 0+1
Answer: d