Memory Allocation Strategies In which storage placement strategy is a program placed into the smallest available free hole (partition) in main memory?

Introduction / Context:
Dynamic memory allocation in operating systems or allocators often uses placement strategies to choose where to place a new block. Best fit, first fit, and worst fit are classic policies with different fragmentation characteristics.

Given Data / Assumptions:

• Variable-sized free memory holes available for allocation.
• Goal is to select a hole for an incoming request of size S.

Concept / Approach:
Best fit finds the smallest hole that is still large enough for S, aiming to leave minimal leftover space. First fit uses the first adequate hole encountered. Worst fit chooses the largest hole to reduce the number of small fragments (with mixed results). Buddy systems split memory in powers of two.

Step-by-Step Solution:
Scan free list for holes >= S.Select the smallest qualifying hole (best fit).Allocate S; if leftover remains, it becomes a smaller free hole.

Verification / Alternative check:
Simulate allocations and measure external fragmentation. Best fit tends to create many tiny holes, while first fit is faster and may fragment differently. Observations confirm best fit chooses the smallest adequate hole.

Why Other Options Are Wrong:
First fit (Option B) chooses the first adequate hole, not necessarily the smallest.Worst fit (Option C) deliberately chooses the largest hole.Buddy (Option D) uses power-of-two blocks, not arbitrary smallest holes.

Common Pitfalls:

• Assuming best fit always minimizes fragmentation; it may produce unusable slivers.
• Ignoring allocation speed differences among strategies.

Final Answer:
Best fit.