Problem Statement
What is an extent-based allocation in a file system and why is it preferred for large files?
Explanation
Extent-based allocation assigns a file one or more large contiguous regions (extents) of disk blocks rather than many small scattered blocks. This reduces fragmentation, improves I/O performance for large sequential reads/writes, and simplifies block mapping. Many modern file systems such as XFS and ext4 use extents for scalability and performance. Demonstrating knowledge of extents can impress interviewers. :contentReference[oaicite:5]{index=5}
