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First fit, Best fit and Worst fit in operating system-oocomputer world

 First fit 

Allocate the first hole that is large enough. In other word we can say that In the first fit the partition is allocated which is the first block from the top of the main memory. So it scan memory from the beginning and choose the first block that is large enough.

Advantage of first fit memory allocation

  1. It is fast in processing
  2. It is very fast in execution

Disadvantage of first fit memory allocation

  1. It west lot of memory.

Best fit

Allocate the smallest hole that is big enough. In other words we can say that in the best fit, allocate the process to the partition which is the smallest sufficient partition among the free available.

Advantage of best fit allocation

  1.   The operating system allocates the job minimum possible space in the memory making, memory management very efficient.
  2. To save memory from getting wasted, it is the best method.

Disadvantage of best fit allocation

  1. It is a slow process 
  2. It takes lot of time to complete the work 

 First fit, Best fit and Worst fit in operating system-oocomputer world

Worst fit

 Allocate the largest hole. In another word we can say that in the breast fit,  it a allocate the process to the partition which is the largest sufficient among the freely partitions available in the main memory.

 Advantage of worst fit allocation

  1.  The process choose the largest hole, therefore there will be large internal fragmentation.
  2. This internal fragmentation will be quite big so that other small process can be placed in that field over partition.

Disadvantage of word fit allocation

  1. It is a slow process.




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