SystemStorage

Question 1

What are the two main categories of physical storage based on power dependency?

Answer 1

Volatile and Non-volatile storage

Question 2

What is the key characteristic of volatile storage?

Answer 2

It loses its contents when power is switched off

Question 3

What is the key characteristic of non-volatile storage?

Answer 3

It retains its contents even when power is switched off

Question 4

What is the primary example of volatile storage?

Answer 4

Random Access Memory (RAM)

Question 5

What are the 7 factors to consider when selecting storage solutions?

Answer 5

Access Speed Capacity Cost Reliability Power Consumption Physical Size Scalability

Question 6

What is the access time of L1 Cache?

Answer 6

Less than 1 nanosecond

Question 7

What are the three main levels of storage hierarchy groups?

Answer 7

Primary storage (volatile) Secondary storage (online) Tertiary storage (offline)

Question 8

What are the 3 main storage interfaces?

Answer 8

SATA SAS NVMe

Question 9

What is the maximum data transfer speed of SATA 3.0?

Answer 9

6 Gbps

Question 10

What is the maximum data transfer speed of SAS-3?

Answer 10

12 Gbps

Question 11

What are the key components of an HDD?

Answer 11

Platters Read/Write Heads Actuator Arm Spindle

Question 12

What is a sector in HDD?

Answer 12

The smallest unit of data that can be read/written (typically 512 bytes)

Question 13

What are the two components of HDD access time?

Answer 13

Seek Time and Rotational Latency

Question 14

What are the main components of an SSD?

Answer 14

NAND Flash Memory Controller Cache Host Interface

Question 15

What is wear leveling in SSDs?

Answer 15

Technique to assign “cold data” to frequently erased pages and “hot data” to less erased pages

Question 16

What is RAID?

Answer 16

Redundant Array of Independent Disks - technology combining multiple disk drives into a logical unit

Question 17

What is the key feature of RAID 0?

Answer 17

Data striping across drives with no redundancy

Question 18

What is the key feature of RAID 1?

Answer 18

Data mirroring across two or more drives

Question 19

What is the key feature of RAID 5?

Answer 19

Striping with distributed parity across all drives

Question 20

What’s the difference between SAN and NAS?

Answer 20

SAN provides block-level access while NAS provides file-level access

Question 21

What is the typical access time range for RAM?

Answer 21

50-100 nanoseconds

Question 22

What is the typical access time range for SSDs?

Answer 22

20-100 microseconds

Question 23

What is the typical access time range for HDDs?

Answer 23

5-10 milliseconds

Question 24

What is the main advantage of NVMe over SATA?

Answer 24

Lower latency and higher throughput due to direct CPU connection

Question 25

What is the purpose of CPU cache?

Answer 25

To store frequently accessed data and instructions

Question 26

What is the capacity utilization of RAID 1?

Answer 26

50% of total drive capacity

Question 27

What is the purpose of garbage collection in SSDs?

Answer 27

Reclaims space from deleted data

Question 28

How many erase cycles can a typical NAND flash cell endure?

Answer 28

100000 to 1000000 erases

Question 29

What is the function of the HDD controller?

Answer 29

Interface between computer system and hardware accepts high-level commands

Question 30

What is data striping?

Answer 30

Technique of splitting data across multiple drives to improve performance

Question 31

What components make up the storage hierarchy from fastest to slowest?

Answer 31

CPU Registers -> CPU Cache -> RAM -> SSD -> HDD -> Network Storage -> Tape Archives

Question 32

What is the primary advantage of RAID 6 over RAID 5?

Answer 32

Better reliability due to double parity blocks

Question 33

What is hot swapping in RAID systems?

Answer 33

Ability to replace disk while system is running

Question 34

What is data scrubbing in RAID?

Answer 34

Continually scanning for latent failures

Question 35

What is the primary use case for RAID 10?

Answer 35

High-performance databases requiring both redundancy and speed