When you format HDD or a flash drive, you prepare them for storing information by the operating system. During formatting, all information is deleted and a clean file system is installed.

You may have heard of FAT or NTFS file system, but do you know which one is used on your system? This article explains how the file system is structured and what the differences are between different file systems. I'll also show you how to find out what file systems your drives are using.

What is a file system?

Disk space is divided into sectors, each of which is approximately 512 bytes in size. Sectors are grouped into clusters. Clusters, also called allocation blocks, range in size from 512 bytes to 64 kilobytes because they are typically made up of multiple sectors. Clusters are contiguous blocks of disk space.

Operating systems rely on the file system to organize clustered information storage. The file system is a database that contains information about the state of each cluster. Essentially, the file system tells the operating system in which cluster (or clusters) the file is stored, and where new data can be written.

What file systems should you know about?

Basically, Windows OS uses FAT (File Allocation Table), FAT32 and NTFS (New Technology File System) file system.

In short, NTFS can store files larger than 4 GB, and partitions can be larger than 32 GB. NTFS manages free space better than the FAT or FAT32 file system and therefore results in less disk fragmentation. NTFS also supports some security features, including on-the-fly file encryption.

Compared to NTFS, file FAT systems and FAT32 accommodate smaller space, are less hard drive intensive, and therefore work faster with small flash drives. In addition, FAT and FAT32 are cross-platform file systems. The main disadvantage of FAT and FAT32 is the 32 GB partition size limit, as well as the 2 GB and 4 GB file size limit, respectively.

To store information on flash drives, the new file system exFAT (Extended File Allocation Table), also known as FAT64, is mainly used. Like NTFS, it supports files larger than 4 GB and partitions larger than 32 GB, and its file management system avoids disk fragmentation. At the same time, it is fast, optimized for mobile media and media file processing.

What operating systems work with these file systems?

FAT and FAT32 are available for reading/writing in almost all operating systems Oh. Previously, formatting a disk for the NTFS file system was the right way make it inoperable outside of Windows OS. However, NTFS read/write support is now built into many Linux distributions. There is also a hack that allows you to work with this file system on Mac OS X version 10.6, although it seems to be unstable, so using MacFuse is recommended. On the other hand, exFAT requires installation of drivers in both Windows XP and Linux and is supported by the latter Windows versions(Vista SP1, Windows 7, 8) and Mac OS X.

Why is cluster size important?

If you have already formatted the disk, you should know that you can select the cluster size (or allocation block size).

Depending on the cluster size (from 512 bytes to 64 kilobytes), the file can be stored in one or hundreds or thousands of clusters. When the file size is smaller than the cluster size, the remaining space is wasted. This phenomenon is called "lost space". Consequently, storing many small files on a disk with a large cluster size will result in large amounts of wasted space. On the other hand, if we choose a small cluster size, large files will be broken into many small pieces, which can slow down disk operations since it will take more time to read the corresponding file. In other words, choose your cluster size wisely.

How to find out the file system type on a disk?

The file system is specified in the disk properties. Go to My Computer, right-click on the desired disk and further in context menu select Properties. In the General tab, in the File system line ( File system) you will see the type file system.

To find out the cluster size of a disk with the NTFS file system, use the key combination + [R], the Run window will open. Make sure you are logged in as a user with administrative rights. In the Run a program window, type cmd in the text box and click OK. Next, enter the command > fsutil fsinfo ntfsinfo and press Enter.

In Windows XP and Windows 7, you can also view and change the cluster size using third-party applications such as .

What file system do you prefer to use on disks and why? Have you encountered problems when using file NTFS systems, and how did you solve these problems?

Sooner or later, on any computer you need to perform a procedure such as formatting the disk. Moreover, in order to launch it, the system needs to answer the question of what cluster size to set, which often confuses novice (and not only) PC users.

How is data stored on a computer?

To understand the best disk cluster size to choose, you need to consider its operation as a whole. If we simplify everything very much, we can figuratively imagine the memory of a drive in the form of a room, along the walls of which there are many numbered small drawers.

There will be a separate directory (disk map), which is needed so that the system does not review all the “boxes”, but immediately knows, for example, that a file with a certain audio recording is in boxes numbered from 45 to 62. It may also be the case that When writing the file to memory, there were no empty boxes in a row, and the computer wrote the file into boxes from 45 to 50 and from 65 to 77.

Accordingly, this is displayed in the directory, and when the system needs to get a file for work, it “looks” at the disk map and “pulls out” the desired entry from the drawers. The size of the cluster can be figuratively compared with the size of the box.

Here you need to take into account the fact that the computer cannot put pieces of different files in one box, otherwise there will be confusion in the directory. Accordingly, the file or part of it may occupy the entire volume of the box, or it may be less. From the above example it is clear that the volume of one box is the minimum possible unit of memory allocated to store a piece of a file, which is called the “cluster size”.

Why format?

First of all, this operation is done to completely clean the disk. If its space is occupied by many files, then when deleting them normally, the system will erase them one by one, which in some cases may affect the speed of the entire procedure as a whole.

If you perform formatting, then it is not necessary to physically delete data from each cell separately - you can select an option such as “quick clear table of contents”. This method does not erase the entire contents of the disk, but only the entries from the directory. The system will be given a command to perceive the clusters as not containing data; accordingly, when writing a new file, the old data will simply be replaced with new ones. Some recovery programs use this deleted files- until something new is written to the clusters, their former contents can still be retrieved.

The second reason why you need to decide what cluster size to choose when formatting is a change in the file system.

Differences between disk layouts

If we continue the analogy with a room filled with boxes, it will be clear that there can be various ways organize the data in them, as well as systematize entries in the catalog. Each of these methods will be called a separate file system, with its own advantages and disadvantages.

Which one will be used depends primarily on the operating system and how you plan to use the computer itself, and how large the files will be stored in its memory.

It should be noted here that the concept of “cluster” refers to layouts created for Windows operating systems and some Macs from Apple.

File system FAT

This markup hard drive used in operating rooms DOS systems and early Windows, up to version XP. It was with her that the concept of “cluster size” took on the meaning of the minimum section of a hard drive that can be allocated for data storage.

Clarification! Physically, the smallest section of a disk with data is a sector with a volume of 512 Bytes, of which a cluster, depending on the file system and OS, can contain from 1 to 128 pieces. Accordingly, its size can be from 512 Bytes to 64 KB.

FAT itself exists in three versions, which differ in the length of the cluster number entry in the directory. These are FAT 12, 16 and 32. It is clear that the longer the “box” number can be, the more of them can be “seen” by the computer OS.

Disadvantages and limitations of FAT file systems

The other side of the coin is that if there are more of these boxes than the system can “see,” then not all of them will be used, but only those with enough numbers. Because of this, a large hard drive may either not be formatted with this file system at all, or show less capacity after the operation.

Another disadvantage is that if the cluster occupies several sectors, then there may be a loss of free space, because if it is 32 KB, and only 1 KB is occupied, then the remaining 31 will remain unoccupied.

The restrictions if you use the minimum and maximum cluster size when formatting will be the following:

*Due to OS features.

**Some programs or operating systems that support FAT are theoretically capable of reading clusters larger than 32 KB. In such cases, the limit would be 64 KB and twice the maximum disk size. But the loss of space in this case reached 50% and the question of what cluster size to choose was unnecessary - it is much more profitable to divide the disk into 2 parts and use a “box” with a capacity of no more than 32 KB.

NTFS file system

Created to replace outdated versions FAT, to support large disks and new technologies introduced into operating systems. It differs from its predecessors primarily in the possible number of clusters, the number of which can reach 2 48 . This allows you to use NTFS on disks with a capacity of 16 Exabytes (16 million Terabytes), and the size of the files used is limited only by the capacity of the media.

If the cluster size when formatting NTFS partitions can be chosen approximately, like its predecessors - from 512 Bytes to 64 KB, then the file system's security capabilities are an order of magnitude higher. Its records can respect the access rights of several computer owners, it is possible to assign quotas of available disk space, and in addition, the files themselves are protected from failures, for example, during a power outage.

Since this file system is far from exhausting its resources, it will take a long time to decide what cluster size needs to be set based on its example.

What does the size of the cluster affect - as a result

The biggest problem it can create is excess unused disk space. But only if there are a lot of small files on the disk. For clarity, you need to imagine that there is a 1 TB drive, it is completely occupied by various files - video, audio and text documents, and each of the files takes up an extra cluster (it is either smaller or larger - in any case there is unused space).

By default, the cluster size when formatting is set to 4 KB. Moreover, if there are 100 thousand on the disk text documents, 100 bytes each, the loss will be 460 megabytes.

Important! It must be remembered that the larger the cluster size, the less load on the hard drive.

The table shows that if the disk is not planned to store a large number of small files, i.e. it is intended for music and movies, then it is best to set the maximum cluster size. Otherwise, you need to choose between the desire to save a few hundred megabytes and a potentially greater load on the drive of the media, and in addition, think about whether it will contain 100 thousand small files.

Special attention should be paid to the system partition of the disk on which the system is installed. If during its installation the volume is formatted third party programs, allowing you to select the cluster size, it is worth remembering that only in Windows folder contains about 90 thousand files, and about 50 thousand more in the user folder... Therefore, here it is better to leave the golden mean offered by the system.

(hard drive or flash drive) is not a whole piece, but a system of memory cells called clusters. Each of them is assigned a unique serial number. In other words, all memory is divided into blocks.

Now let's look at what cluster size is. It's simple, it's a certain size of one disk memory cell. By using modern instruments you can set absolutely any value. Sets the cluster size when formatting. It can be at least five hundred twelve bytes and higher. This will depend on your goals.

Now let's figure out why this cluster size is set. This is done to properly store your information on one or another medium. This also affects the optimization of device operation. You should always proceed from what the device will be used for. As mentioned earlier, the cluster size is determined during formatting of the information storage device. The first to allow users to do this on their own was the operating room. Windows system XP.

Before starting this process, you must select the file system type. For removable drives, it is always better to set FAT 32. This is done so that they are accepted by any devices. It is also worth leaving the cluster size as standard. NTFS is more suitable for hard drives. True, in this case, your device will not be available in operating systems such as Windows 98 and the like.

After you decide on the file system, you need to set the cluster size. If this is not done, the system will set the standard size, which will be equal to four kilobytes. What should you consider when choosing a size? The smaller the cluster, the more data you can put on your storage device. For example, if you make the cluster volume large enough, a file with a smaller volume will still occupy the entire cluster. However, in this case, all data from the disk will increase significantly. If you set the size to one kilobyte, then files of similar sizes will occupy only this cell and no more. This will also give an advantage in cases where you remove the flash drive without using it. In such a situation, fewer clusters will be damaged. However, the speed of reading information will decrease significantly.

Therefore, you should base it on what you will be using the device for. If you plan to keep a film library on one of the partitions of your hard drive, then you can format it with maximum dimensions clusters. This will enable the disk to process and reproduce the data recorded on it much faster. If this happens system disk, then its clusters should not exceed the standard size. Otherwise, you will lose a lot of useful space, because operating systems contain a lot of small files. In addition, this will lead to the disk spending a large amount of time processing data.

Users of any operating system have at least once encountered the concept of a cluster. This word means a certain value, which refers to the size of the cell for storing files. Typically this size depends on the storage capacity of the media.

You will need

• Windows operating system.

Instructions

10. 06.2018

Blog of Dmitry Vassiyarov.

I can’t decide which cluster size to choose when formatting

Greetings to my readers, and today I am very pleased to move from theory closer to practice. Today we will find out what cluster size to choose when formatting NTFS. It is NTFS that most users often use, so let’s touch on it. This is a real problem that comes up all the time when preparing a hard drive for reinstalling Windows. And also in other situations.

First, let's remember what a cluster and NTFS are and what is the connection between these concepts. So, the computer memory (or flash drive, or memory card) is divided into separate sectors of 512 bytes or 4 KB, which in turn are grouped into clusters. Accordingly, the cluster size is a multiple of the sector volume.

But I sincerely wish you confidence and computer intuition that will help you choose the optimal cluster size. With this I will finish and say goodbye to you.

See you soon in new topics on my blog.