The document discusses the responsibilities and functions of an operating system's memory manager. The memory manager must securely allocate memory in a way that prevents memory leaks and stack overflows. It allocates memory dynamically using different techniques, including fixed and dynamic block allocation, dynamic page allocation, and dynamic address relocation. The memory manager also protects memory access between the operating system functions and tasks running on the system.

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J.SUDARSHANREDDY

2.  The memory manager of the OS has to be secure ,
robust and well protected . There must be control
such that there are no memory leaks and stack
over flows.
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3. MEMORY IEAKS:-
It means attempts to write in the memory
block not allocated to a process or data structure.
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4. An memory provides for dynamic memory
allocation and de-allocation :
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5.  Fixed blocks allocation
 Dynamic blocks allocation
 Dynamic page allocation
 Dynamic data memory allocation
 Dynamic address relocation
 Multi processor memory allocation
 Memory protection to OS functions
 Memory protection among the task
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6.  It having small address space getting a lesser
number of blocks and process with big address
spaces getting a larger number of blocks.
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7.  This block is a fixed blocks and then later the
memory manager later allocates variable size
blocks dynamically allocated from a free list of
memory blocks description table at the different
computation phases of process.
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8.  Memory has fixed size blocks called pages and
the memory manager MMU allocates the pages
dynamically with a page descriptor table.
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9.  The manager dynamically allocates the addresses
initially bound to the relative addresses.
 The memory manager now dynamically changes
only the contents of relocation register . It also
takes into account a limit defining register so that
the relocated addresses are within the limit of
available addresses . This is also called “run time
dynamic address binding”
1/25/2015J.SUDARSHANREDDY

10.  Memory protections to the OS functions means
that the system call and function call in our space
are distinct . The OS function code , data and
stack are in the protected memory area . It means
that when a user function call attempts to write or
read in the exclusive memory space allocated to
the OS functions , it is blocked and the system
generates an error . The memory of kernel functions
is distinct and can be addressed only by the system
calls . The memory space is called kernel space.
1/25/2015J.SUDARSHANREDDY

11.  Memory protection to the task means that
a task function call cannot attempt to the
write or read in the exclusive area of
memory space allocated to another task .
The protection increases the memory
requirement for each task and also the
execution time of the code of the task.
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12. Thank you
1/25/2015J.SUDARSHANREDDY