Page table
Page tables are tables used to keep track of the memory alloted to any sub part of a process. Actually a process is divided into different parts: say a process A is sub divided into 4 equal parts (A.0, A.1, A.2, A.3), and each of these is called Page.
WHY CREATE PAGE TABLES?
Page tables are used to keep track of the currently required portion of the process and to load only that part into the memory so that the undesired process portions are kept away form residing in the main memory needlessly.
Here comes the need to keep track that what part (PAGE) of the process is stored at which location of the memory. This is achieved through PAGE tables. The format of a page table is like page#,Frame#.
|---------|----------|--------|----------|---------|-------------|
|caching |Referenced|Modified|Protection|Present/ |Page Frame |
|disabled | | | |Absent |Number |
|---------|----------|--------|----------|---------|-------------|
The Fromat of a PAGE Table
|-------| |--|
| page 0| | 2|
|-------| |--|
| page 1| | 6|
|-------| |--|
| page 2| | 4|
|-------| |--|
| page 3| |10| PAGE TABLE FOR THE PROCESS a
------- |--|
Logical Memory (For process a)
frame
Numbers
|-------|
0| |
1|-------|
2| page 0|
3|-------|
4| page 2|
5|-------|
6| page 1| |
7|-------|
8| |
9|-------|
10| page 3|
11|-------|
12| |
13|-------|
14| |
-------
Physical Memory
