RAID

Question 1

RAID 0

Answer 1

split across multiple disks

Question 2

Benefits/Faults RAID 0

Answer 2

high read/write speeds
no fault tolerance

Question 3

Raid 1

Answer 3

duplicated across multiple disks

Question 4

Benefits/Not RAID 1

Answer 4

high redundancy
reduced storage capacity and preformance

Question 5

RAID 5

Answer 5

data is stiped across multiple disks
parity information is distributed

Question 6

Benefits/NOT RAID 5

Answer 6

can allow for drive failure without loss
slower write speeds

Question 7

Primary Storage

Answer 7

volatile
fastest media
cache, main memory

Question 8

secondary storage

Answer 8

non volatile
moderately fast
flash memory, magnetic disks
on-line storage

Question 9

tertiary storage

Answer 9

non volatile
slow access time
off line storage
lowest level

Question 10

RAID

Answer 10

redundant arrays of independent disks

Question 11

Disk organization technique

Answer 11

improve reliability : storing data redundantly
improve performance: using disks in parallel

Question 12

Parity blocks

Answer 12

• stores XOR bit from block j of each disk
  *recompute parity when writing to j
• recover data of block through XOR of bits from all other blocks and parity block

Question 13

Buffer Manager

Answer 13

• retrieval of block from disk

Question 14

in/not in buffer

Answer 14

• address of memory returned
• allocate space for block
• evict other blocks for space (need?)
• write evicted block to disk if it was update after being fetched
• read block from disk to buffer, return address of block in main memory