if I have a 50GB transfer as a bunch of big files and a 50GB transfer as lots of very small files, why is the first one faster in Windows?

Question

I’m moving a bunch of files for some drive changes, and I’ve noticed a bunch of times that for 2 equally sized data transfers, the smaller and more number of files the slower it goes. Why does this happen?

In: 3

Answer 1

Imagine having to move 1000 liters of water in containers.

One batch is in approximately 1000 drinking bottles of various sizes.
Another batch is in approx 10 big containers.
Which batch will be faster to move?

Computers work in a similar way. Every single file has a bunch of overhead called metadata (such as file name, size, timestamps) that need to be recorded, making the transfer time depend on both the number of files as well as the amount of data.

EditLI5: “ca.” (circa) changed to “approximately”