Does larger disk allocation unit size in HDD makes file searching faster?

Question

Does choosing a larger unit size make it perform faster when it comes to searching files in the disk drive or even writing/reading files? Larger allocation unit means the hard disk needle needs less block addresses to check when searching a certain file. Does it make file search faster?

I will give 1GB of wasted disk space for this. I currently have 25,372 files below 32KB in my hard drive and that sums up to 831MiB size on disk of total space for the 25,372 files which only have 37MB of actual file size.

Answer 1

Larger allocation size may mean more internal fragmentation and small allocation size may mean larger external fragmentation. Operating Systems Concepts(Take a look at page 387, section 8.3.3)

You should probably just use whatever is default.

Indexing the file will improve search times.

Read and write times have more to do with your hardware (hard disk, CPU, RAM),your OS design and your USB capability for your computer (2.0, 3.0 etc.). Computer Organization and Design see Chapter 5 page 477.

Answer 2

Increasing the allocation size can speed up disk seek times. The larger the allocation unit, more file data can be placed in that unit. The fewer units a file is in, the less a disk has to seek to find the data. When files are placed in non-contiguous blocks, this is called fragmentation. If the disk has to jump around the platter to find all the pieces of a file, that can slow it down. However, there is a drawback to larger allocation sizes - wasted space. Even if a file uses 1 byte of a block, the rest of that space is wasted, as no other file can use it.

For most users, the default allocation size is fine.