Sunday 1 September 2013

Task  , Process  &  Thread  are interlinked hierarchy ,  yet they are different .
this  hierarchy can be represented  as...

  • A  Task  is set of program instructions that are loaded in memory. 
  • A  Process  is an instance of a computer program being executed. It  conatins  the program code and its current  activity . 
  • A  Thread  of execution results from a fork of a computer program into two or more concurrently running   task.


 HOW THREADS ARE DIFFERENT FROM PROCESS

A thread is contained inside process.  Multiple threads can exist  witin the same process and share resources such as memory , while different process do not share these resources.
 A thread what CPU actually runs , its about scheduling access to shared resources e.g. CPU .
A process is the allocated memory for instruction data (a process needs one or more threads because that is what is run by CPU ) , simply we hink of thread as a slice of time and a process as a slice of space .
shortly............. :)
  • processes are typically independent , while threads exists as subset of process.
  •  processes have seprate address spaces , where as threads share their adress spaces .



        
             

5 comments:

  1. WHAT DO U MEAN BY SHARING OF ADDRESS SPACE???
    HOW AN ADRESS SPACE WILL BE SHAREED BY A THREAD???

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  2. both process and threads are independent sequence of execution . typical difference is that threads (of same process) run in a shared memory space while process run in seperate memory space. thread are an operating environment feature , rather then cpu feature .

    sharing of add. space term is used for threads only..... could be explain furthur

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  3. as for improving the interprocessing within a process threads are formed (these r light weight process ) . There is one address space for whole process & different threads(belong to same process) share everything like objects , heaps etc... to reduce context switching time and reusing info required for processing again and again.

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  4. ok....agree with ur explaination.. !!!

    ReplyDelete