In the case of the best fit memory allocation scheme, the operating system searches for the empty memory block. When the operating system finds the memory block with minimum wastage of memory, it is allocated to the process.

How does it work?

In Best fit memory allocation scheme, the operating system searches that can –

• Accommodate the process
• Also, leaves the minimum memory wastage

Example:

If you see the image right you will see that the process size is 40.

While blocks 1, 2 and 4 can accommodate the process. Block 2 is chosen as it leaves the lowest memory wastage

1. Efficient Memory Usage: It tries to reduce the wastage of space because it allocated the smallest appropriate holes for requesting process.

1. It requires O(n) time to search the entire list and find the smallest one.
2. As if it chooses the smallest possible space, so the very small size of hole is free and not fit farther for any process.

Simulations

MVT-Best fit Simulation

Try out best fit allocation in variable task with visualising the process allocation in main memory

Go to simulator

MFT-Best fit Simulation

Try out best fit allocation in fixed task with visualising the process allocation in main memory

Go to simulator