Explain the concept of thread, Computer Engineering

Assignment Help:

The Concept of Thread

A thread is a sequential flow of control within a process. A process is able to have one or more threads. Threads have their own register-values and program-counter but they share memory space and other resources of the process. Every process begins with a single thread. Through the execution, other threads can be created as and when required. Similar to processes, every thread has an execution state (terminated, ready, blocked or running). A thread has right to use the memory address space and resources of its process. Threads have similar life cycles as processes do. A single processor system may support concurrency by switching execution among two or more threads. A multi processor system may support parallel concurrency by executing a separate thread on every processor. There are three fundamental techniques in concurrent programming languages for terminating and creating threads: 

  • Unsynchronised creation and termination - In this mode threads are created and terminated by means of library functions for example START_PROCESS, CREATE_PROCESS, START_THREAD, CREATE_THREAD and. Thus because of these function calls a new thread or process is created and starts executing independent of its parents.
  • Synchronized termination and unsynchronised creation: This manner uses two instructions: JOIN and FORK. The FORK instruction creates a new thread or process. When the parent needs the child's (thread or process) result, it calls JOIN instruction. At this junction two processes (threads) are synchronised.
  • Synchronised termination and creation: The most often system construct to implement synchronization is COBEGIN...COEND. The threads among the COBEGIN...COEND construct are implemented in parallel. The termination of parent-child is suspended till all child threads are terminated.

We can think of a thread as essentially a lightweight process. Though, threads propose a number of advantages over processes. The advantages are as follows:

a)  It does not take so much time to create and terminate a new thread than to create and terminate a process. The reason is that a newly created thread uses the current process address space.  

b)  It does not take so much time to switch between two threads within a common process, partly since the newly created thread uses current process address space. 

c)  Less communication overheads -- communicating between the threads of one process is simple since the threads share amongst other entities the address space. So, data generated by one thread is right away available to all other threads.


Related Discussions:- Explain the concept of thread

Does c have circular shift operators, No C don't have circular shift operat...

No C don't have circular shift operator. (Part of the reason why that is the sizes of C's types aren't precisely described----but a circular shift makes most sense when applied to

menu-driven program, Write a menu-driven program to change a time in secon...

Write a menu-driven program to change a time in seconds to other units (minutes, hours, etc.).  The main script will loop to continue until the user chooses to exit.  Every time in

Find max conversion time of 6-bit dual slope A/D converter, A 6-bit Dual Sl...

A 6-bit Dual Slope A/D converter uses a reference of -6V and a 1 MHz clock. It uses a fixed count of 40 (101000). Find Maximum Conversion Time.         Ans. The time T 1 specifie

Explain why most interrupts are active low, Explain why most interrupts are...

Explain why most interrupts are active low? This answers why most signals are active low when you see the transistor level of a module, active low implies that the capacitor in

Shared memory and distributed memory, Shared Memory Refers to the memor...

Shared Memory Refers to the memory part of a computer system in which the memory can processed directly by any of the processors in the system. Distributed Memory Refer

Ms access database through menu driven selections, Would you like to easily...

Would you like to easily automate your MS Access database through menu driven selections? This can be accomplished by producing a form with customized buttons that point to macr

List the allowed register pairs of 8085, List the allowed register pairs of...

List the allowed register pairs of 8085. B-C register pair D-E register pair H-L register pair

Advantages to companies adopting call centres, Advantages to companies adop...

Advantages to companies adopting call centres Computer systems have allowed companies to set up call centres in other nations where potential cost savings can be made. This, of

Super class and subclass in programming, What is the difference among super...

What is the difference among super class and subclass in programming? Ans) A super class is a class that is inherited in programming while the sub class is a class that does th

Specify the default alignment, Specify the default alignment for the follow...

Specify the default alignment for the following field types: 'D' - Left, 'F'-Right, 'N'-Left, 'I'-Right, 'T'-Left.

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd