Question

• What is the difference between a process and a thread?
• What prevents complete thread independence? Give one specific example of a dependency.
• What are the advantages/disadvantages of designing a concurrent program using threads versus events?

Answer 1

1. Difference between process and threads are listed below

Process	Threads
Execution of a program	Execution of a program driven by the environment of a process
isolated from other processes	share memory and resources with eachother between threads
Needs more resources	uses less resources
Less efficient comparatively in communication	enhances efficiency in case of communication
Creation time is more	creation time is less
Termination time is more	Less termination time

2. Threads are independent like process such that it has own program counter, register set , stack space and also the allocated time. But threads are not completely independent since it shares the code section, data section and is resources with other threads

3. The advantages are,

• Enhanced performance by decreased development time.
• Simplified and streamlined program coding.
• Improvised GUI responsiveness.
• Simultaneous and parallelized occurrence of tasks.
• Better use of cache storage by utilization of resources.
• Decreased cost of maintenance.
• Better use of CPU resource.

The disadvantages are,

• Complex debugging and testing processes
• Overhead switching of context
• Increased potential for deadlock occurrence
• Increased difficulty level in writing a program
• Produces unpredictable results