What is a kernel-level thread scheduler?

The kernel-level thread scheduler is part of the OS kernel responsible for scheduling kernel threads. It uses algorithms like:

• Round-robin
• Multilevel feedback queues
• Priority-based scheduling

How do thread priorities affect scheduling?

Higher priority threads are planned to execute before lower priority threads. However, lower-priority threads may experience thread hunger if priorities are overused.

What is a context switch in a multithreaded environment?

In a multithreaded environment, a context switch is the process of moving between threads, necessitating the saving and restoration of their execution states and CPU registers

How do you measure thread performance?

Thread performance can be measured using:

1. Thread Execution Time: Time spent in active execution.
2. Thread Latency: Time taken to start or resume.
3. CPU Utilization: Percentage of CPU time utilized by threads.
4. Scalability: How well threads scale with additional cores/processors.

What is the difference between implicit and explicit threading?

• Implicit Threading: Threads are managed automatically by libraries or frameworks (e.g., OpenMP).
• Explicit Threading: Developers manually create and manage threads using threading APIs.

What are thread-safe data structures?

Thread-safe data structures ensure proper synchronization when accessed by multiple threads. Examples include:

• Concurrent queues
• Atomic variables
• Synchronized collections in Java

How do threads interact with virtual memory?

In a multithreaded environment, a context switch is the process of moving between threads, necessitating the saving and restoration of their execution states and CPU registers.

What is the Thread Control Block (TCB)?

The Thread Control Block (TCB) is a data structure maintained by the OS to store thread-specific information, such as:

• Thread ID
• Register state
• Stack pointer
• Scheduling information

What tools are used to analyze thread performance?

• Valgrind (Helgrind): Detects race conditions.
• Intel VTune: Analyzes thread performance on Intel CPUs.
• Perf: Linux performance analysis tool.
• Thread Sanitizer: Finds data races in programs

What is memory management?

Coordinating and managing computer memory, assigning sections to processes, and recovering memory when it is no longer required is known as memory management. It guarantees effective use of memory resources.

What are the main tasks of memory management?

• Memory Allocation: Assign memory to processes.
• Memory Protection: Prevent one process from accessing another’s memory.
• Swapping: Move processes between main memory and disk storage.
• Virtual Memory Management: Simulate more memory than physically available.

What is the difference between physical and logical addresses?

• Physical Address: The actual address in memory hardware.
• Logical Address: The address generated by the CPU, translated to a physical address by the Memory Management Unit (MMU).