multitasking - the ability to execute more then one task at same time

Q1) Is it correct definition for multitasking?

task has three state
running-executing on cpu
ready-read to be execute
waiting - waiting for execution

If we have two task running at same time, both task can not be executed at same time so one of them will be delayed , one task will be wait another task will be execute

Q2) one task will be wait another task will be execute but what decide that which one will be execute first and which one will be wait?

I am confused about what is multitasking and scheduling

 

http://en.wikipedia.org/wiki/Computer_multitasking
http://en.wikipedia.org/wiki/Scheduling_(computing)

 

check out this definition
kernel -kernel is part of operating system that provide basic service to application software running on processor

multitasking - multitasking is process where one or more task run at same time on same single processor

scheduling- scheduling is process by which operating system decide which one task will be perform first on processor

please correct me If I am wrong

 

check out this definition
kernel -kernel is part of operating system that provide basic service to application software running on processor

multitasking - multitasking is process where one or more task run at same time on same single processor

scheduling- scheduling is process by which operating system decide which one task will be perform first on processor

please correct me If I am wrong

Minor nit-picking points...

multitasking - multitasking is process where one or more task appear to run at same time on same single processor

scheduling- scheduling is process by which operating system decide which one task will be next on processor. More generally, scheduling determines the order in which tasks are executed.

 

type of scheduling
First come First serve - task are executed on first come first serve basis
shortest Job first - task execute first which take minimum time to execute
priority based - each task has priority , higher priority task will be executed first

which type of scheduling , rtos support

 

RTOS support does not imply a specific type of scheduling. Different OS kernels may use different scheduling algorithms. The three you listed are not necessarily the only ones. Have you reviewed the Wikipedia article on scheduling?

 

RTOS support does not imply a specific type of scheduling. Different OS kernels may use different scheduling algorithms. The three you listed are not necessarily the only ones. Have you reviewed the Wikipedia article on scheduling?

real time os designer design scheduling algorithms.
Different OS kernels may use different scheduling algorithms

First come First serve -
shortest Job first -
priority based -

Q) can one kernel support three scheduling algorithms ?

Q) does one kernel support only one scheduling algorithms ?

 

memory management for operating system

how to write definition

memory management is part of operating system that is used to store data
memory management is function of operating system that is use to store data

memory management is process of operating system that is uesd to store data

 

memory management for operating system

how to write definition

...

In order to define memory management for an operating systems you start with an inventory of resources. Then you proceed to the methods and procedures for allocating, managing, and recovering blocks of various kinds of memory as they are needed, used, and returned.

 

I'm not clear on what your question implies. Are you looking for a definition that would allow you to implement memory management or are you looking for a definition to input to some kind of simulation tool, or something I can't even imagine.

 

I am asking definition what is memory management in operating system

It is a system application that allocates blocks of memory to a process in such a way that only that process and the operating system can read and write to those blocks. Access to them is denied to all other processes except by well defined process communication methods. When a process is done with a memory block, it releases that block back to the pool of free blocks and the operating system can allocate it to another process.

Are you seriously telling me you could not find this on your own?