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When cleaning old segments, LFS determines that an inode is valid by:

In pure linked allocation, locating the data block at logical offset N within a file may require reading O(N) blocks from disk (assuming nothing is cached).

In ordered (metadata-only) journaling, user data blocks are written to their final in-place locations rather than being copied into the journal.

FFS’s cylinder-group layout eliminates the need for disk seeks when reading an entire large file sequentially.

If two containers are both started from the same 300 MB image, the second container requires roughly another 300 MB of disk space because each container gets its own full copy of the image.

On a hard disk, reading two sectors that are adjacent on the same track is typically much faster than reading two sectors that are on different tracks and far apart on the disk.

Suppose you run a log-structured file system (LFS) on top of an SSD using a log-based flash translation layer (FTL). Both layers do garbage collection or cleaning, meaning they read valid data from a block or segment and rewrite it to the end of the log. Which of the following is true?

Which of the following structures is NOT stored per cylinder group in FFS?

File Systems (Multiple Choice)

What is the main advantage of using DMA (Direct Memory Access) over PIO (Programmed I/O) for transferring a large block of data to a disk?