What is cluster size and how to change cluster size?

When using computer, we may ignore many problems. Most of the time we don’t realize these problems, because these key parameters are fixed or default. To manage our computers better, we must know about the specific meaning of these parameters and know their influences on our computers. Today, I tell you an important noun which we always easily ignore – cluster.  

A track on hard disk disc is divided into several arcs with equal size. The arc is called “sector”. Since the unit of “sector” is too small, sectors are tied together to form a bigger unit to facilitate our management. This unit is named “cluster”, which is the smallest unit for disk file storage management in Microsoft operating system.

In Microsoft operating system, a file is usually stored in one or multiple “clusters”. However, there is limitation that one file at least occupies one “cluster”. That is to say, two or more files can’t occupy one “cluster” at the same time. For instance, there is a file of 3KB, if the size of one cluster is 1 KB, this file needs to occupy 3 “clusters”. If the cluster is 2 KB, this file just need to occupy two clusters. But two clusters are 4KB while the file size is 3 KB. According to the principle that two files can not share one same “cluster”, even if there is a file with 1KB, the file just have to be stored in next cluster. Therefore, 1 KB storage space is wasted. Through the example above we can see that the bigger the cluster is, less cluster the file will occupy. However, the bigger the cluster is, the more disk storage space will be wasted.

If the cluster is smaller, will the storage situation be better? No. It is undisputed that the smaller the cluster is, the higher the computer disk utilization rate will be. But if the cluster is smaller, the computer needs to manage more clusters and plenty of computing resources will be consumed. Besides, if cluster is smaller, computer will produce more disk fragments. All these problems will have grate influence on computer performance. So, a reasonable “cluster” size is the best way to improve computer performance.

How to set reasonable “cluster”? In Windows, there are two kinds of existing file systems FAT32 and NTFS. In FAT 32 file system under Windows 2000, if the partition is 2GB ~8GB, the smallest cluster is 4KB; if the partition is 8GB~16GB, the smallest cluster is 8KB; and if the partition is 16GB~32GB, the smallest cluster reaches 16KB. In Windows 2000 NTFS file system, when partition size is within 2GB, cluster size is smaller than the corresponding FAT32 cluster size; when partition size is beyond 2GB (2GB~2TB), the default cluster size is 4KB. By contrast, we can see that NTFS can more efficiently manage disk space than FAT 32 does, and avoid wasting disk space to a large extent. Therefore, when choosing file system, we’d better choose NTFS file system. And the 4 KB cluster size maybe the most reasonable size. If you store large file such as movie in one partition separately, you can choose to adjust cluster size to bigger one.  

If we are not satisfied with cluster size, how can we adjust the cluster size？ We can turn to system disk management tool to re-choose cluster size through formatting partition. However, this method will cause all data to be lost. Therefore, we’d better use the excellent partition magic alternative MiniTool Partition Wizardto adjust partition cluster size. By this way, we can easily and fast perform operation without causing data loss. Besides, we can convert FAT 32 to NTFS without damaging data with this software, which facilitates performing optimization management for cluster. We’d better keep such a piece of excellent disk management software in our computer.