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

Role of bitmap indexes to solve aggregation problems, Describe about the ro...

Describe about the role of bitmap indexes to solve aggregation problems? Ans) Bitmaps are very useful in begin schema to join large databases to small databases. Answer queries

Analysis the pc configuration, 1) Identify the software needs of each PC an...

1) Identify the software needs of each PC and whether or not anything needs to change. a. State the changes that you would make (and why) b. If no "change" needs to be made b

Define wait protocol, Q. Define Wait protocol? The wait protocol is use...

Q. Define Wait protocol? The wait protocol is used for resolving conflicts that arise due to some multiprocessors requiring same resource. There are 2 kinds of wait protocols:

8259 PIC, plz expalain interfacing of 8259 with 8085 step wise

plz expalain interfacing of 8259 with 8085 step wise

What is dots per inch, Q. What is Dots per Inch? DPI (Dots per Inch) is...

Q. What is Dots per Inch? DPI (Dots per Inch) is a measure for actual sharpness of onscreen image. This relies on both the resolution and size of the image. Practical experienc

Write a short note on pointer operators in c, Write a short note on pointer...

Write a short note on pointer operators in c Pointers (that is, pointer values) are generated with the ''address-of'' operator &, which we can also think of as the ''pointer-to

What is the basic workflow order for color match, Question: (a) What is...

Question: (a) What is the difference between the Color Pass and the Color Replace effects? (b) What is the basic workflow order for Color Match? (c) Explain clearly the

The maximum number of dimensions an array can have in c, The maximum number...

The maximum number of dimensions an array can have in C is C permits arrays of three or more dimensions. The exact limit is examined by the compiler.

Compare the cocomo model with the detailed cocomo model, Compare the basic ...

Compare the basic COCOMO model with the detailed COCOMO model. COCOMO having of a hierarchy of three increasingly detailed and accurate forms. -  Basic COCOMO - is a stati

Software engineering, assignment on transaction flow, transform flow, trans...

assignment on transaction flow, transform flow, transform mapping: refining the architectural design

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