What is the difference between cylinder and cluster?

Answer 1

A cluster is a specific group of bytes, while a cylinder is the actual circular arrangement across multiple platters.

Picture three circles suspended over each other, of equal size. Now divide these into quarters like a pie. Now divide them again into two circular peices. Each circle should now have 8 pieces.

A 'cylinder' would be the circular area across all three circles. IE, the outer 'ring'.

After that, it is divided into sectors. Sectors are then further divided into groups, called clusters. Typically clusters are 512, 1024, 2048, and 4096 bytes, but may be as large at 16 KB.

A cluster is the *smallest* area of space that a file can take up individually. Meaning that if you save a file that is only 156 bytes, and your filesystem is using 16 KB clusters, you will be wasting 15.85 KB of that space!

However files that span multiple clusters require data to be written. In FAT16 and FAT32, this is at the end of each cluster, a small 2-8 byte pointer to find the next cluster the file continues on. In NTFS, this is saved in the MFT (Master File Table). So if you have a 4 KB file and 512 byte clusters, it would actually take 5 clusters worth of space due to the extra data needed to store where each of the clusters are.

Here's a diagram if you're having problems picturing it:

http://www.helpwithpcs.com/jargon/track-sector-example.gif

A 'cylinder' is multiple 'tracks' across all the platters. Like so:

http://www.pctechguide.com/31HardDisk_Format.htm

Answer 2

a cylinder is long and can be used many ways scence its graduated cylinder a cluster is a bunch its like balloons you can put a bunch a balloons together