Chapter 24

Question 1

How can we improve speed

Answer 1

• Hardware architecture
• Software architecture
• Indexing techniques
• Join techniques

Question 2

What is VLDB

Answer 2

very large databases

Question 3

What is parallelism

Answer 3

Divide the data set into pieces and assign to all processors equally. Then the processing has to done independently parallel on all data sets simultaneously

Question 4

Does divide and conquer favors parallelism

Answer 4

Yes

Question 5

What are the requirements for parallelize

Answer 5

All following 4 things

• Parallel architecture (e.g. symmetric multi-processors (SMP), clusters, massively parallel systems (MPP), non-uniform memory access (NUMA) )
• Sufficient I/O bandwidth
• Underutilized CPU
• Sufficiently memory

Question 6

Is it possible that system performance degrade in parallelism

Answer 6

Yes

Question 7

What are the factors for system speed

Answer 7

• Index usage
• Number of concurrent users
• Complexity of technique
• Amount of detailed data
• Complexity of data model
• Underline schema
• Size/scalability

Question 8

What are the 2 methods to upgrade underlying hardware

Answer 8

• Speed up

- Scale up

Question 9

What is speed up

Answer 9

More resources means proportionally less time for given amount of data

Question 10

Does there be linear relationship between degree of parallelism and transaction/sec ideally

Answer 10

Yes

Question 11

What is scale up

Answer 11

If resources increased in proportion to increase in data size, time is constant

Question 12

What is the formula of speed up

Answer 12

Ts/Tm

Question 13

How we quantify speed up in real time

Answer 13

Amdahl’s Law

Question 14

What is parallelism in OLTP

Answer 14

How much transactions can be executed per second

Question 15

What is parallelism in DSS

Answer 15

How big one complex query divides and executed to get result faster

Question 16

What is parallelism in software architecture

Answer 16

• Shared memory

- Shared disk

Question 17

What are other 2 categories of parallelism

Answer 17

Data parallelism

Spatial parallelism

Question 18

What is MPP

Answer 18

In massively parallel systems, every node has independent processor, independent I/O and independent memory. All nodes are connected with interconnection network.

Question 19

Does SMP supports multi tasking and multi processing

Answer 19

Yes

Question 20

What are distributed shared memory machines

Answer 20

Its a combination of both architectures. One software architecture is shared disk RDBMS architecture

Question 21

What is shared disk RDBMS architecture

Answer 21

Database tables are shared. There is a central node and processors access through it to desired section of data.

Question 22

What is memory lock

Answer 22

In RDBMS architecture, memory lock is used to avoid more than one processors trying to access same table/data set.

Question 23

What is disadvantage of memory lock

Answer 23

Process become serialized

Question 24

What is software shared nothing RDBMS architecture

Answer 24

Every processor has its own independent memory. There is no memory locking over here. Once a processor is failed its all memory is gone.

Question 25

Does shared disk RDBMS and shared nothing RDBMS architecture are logical architecture

Answer 25

Yes