Be like that file

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It's a bit tricky to explain what exactly a file system is in just one sentence. Let's start with a simple definition: A file system defines how files are named , stored , and retrieved from a storage device.

Or when you copy, edit, or delete a file, the file system handles it under the hood. However, these concepts remain relevant to other environments and file systems.

Why do we need a file system in the first place, you may ask? Imagine a room with piles of papers scattered all over the place. However, a file system changes everything: A file system isn't just a bookkeeping feature, though.

Everything begins with partitioning Storage devices must be partitioned and formatted before the first use. But what is partitioning? A storage device should have at least one partition or more if needed. Why should we split the storage devices into multiple partitions anyways? The recovery and diagnostic utilities reside in dedicated partitions too.

For instance, the tech team would appreciate a quieter area. Are you ready? Away we go! Wait, what is the system firmware? You may ask. Here's an explanation: A firmware is a low-level software embedded into electronic devices to operate the device, or bootstrap another program to do it. This sector is called MBR. MBR contains the following information: The boot loader, which is a simple program in machine code to initiate the first stage of the booting process A partition table , which contains information about your partitions.

MBR gap can be used to place another piece of the boot loader program if needed. This is when the operating system's logo fades in MBR's data structure limits the number of partitions to only four primary partitions. When making a partition, you can choose between primary and extended. After this is solved, we'll encounter the second limitation. And wait, there's more!

For instance, you can have as many partitions as your operating system allows. This is where the first-stage boot loader would reside in an MBR-partitioned disk After this first sector, the GPT data structures are stored, including the GPT header and the partition entries. This backup is called Secondary GPT. If this path cannot be found on your system, then your firmware is probably BIOS-based firmware.

NVRAM contains the booting settings and paths to the operating system boot loader files. Let's confirm that with the dmidecode command like so: sudo dmidecode -t 0 And the output would be: dmidecode 3. Formatting partitions When partitioning is done, the partitions should be formatted. Most operating systems allow you to format a partition based on a set of file systems.

These data structures are one aspect of a file system. Let's take the NTFS file system as an example. How it started, how it's going A file system is a set of data structures, interfaces, abstractions, and APIs that work together to manage any type of file on any type of storage device, in a consistent manner.

Each operating system uses a particular file system to manage the files. Or you can just use the exFat file system. But how about file systems in Linux distributions? When people talk about file systems, they refer to one of these layers or all three as one unit.

Although these layers are different across operating systems, the concept is the same. The next layer is the virtual file system or VFS. So does this mean an operating system can use multiple file systems at the same time? The answer is yes! Can you guess what it is? Yes, we're talking about the logical file system. A high-level architecture of the file system layers What does it mean to mount a file system? However, there are times you need to mount a file system manually.

Please note that the mount point should already exist as a directory. Inodes are identified by a unique number called the inode number. Inodes are associated with files in a table called inode tables. The inode also includes the address of the blocks allocated to the file; On the other hand, where exactly it's located on the storage device In an ext4 inode, the address of the allocated blocks is stored as a set of data structures called extents within the inode.

Whenever you open a file on Linux, its name is first resolved to an inode number. Having the inode number, the file system fetches the respective inode from the inode table. On NTFS, the metadata is stored differently, though. On most operating systems, you can grab metadata via the graphical user interface. Space Management Storage devices are divided into fixed-sized blocks called sectors. Depending on the file size, the file system allocates one or more blocks to each file.

The layout of a block group within an ext4 partition Each block group has its own data structures and data blocks. Here are the data structures a block group can contain: Super Block: a metadata repository, which contains metadata about the entire file system, such as the total number of blocks in the file system, total blocks in block groups, inodes, and more.

Not all block groups contain the superblock, though. A certain number of block groups store a copy of the super as a backup. Group Descriptors: Group descriptors also contain bookkeeping information for each block group Inode Bitmap: Each block group has its own inode quota for storing files.

A block bitmap is a data structure used to identify used and unused inodes within the block group. The number of inodes stored in this area is related to the block size used by the file system. Data Blocks: This is the zone within the block group where file contents are stored. The layout of the first block group looks like this: The layout of the first block in an ext4 flex block group When a file is being written to a disk, it is written to one or more blocks within a block group.

Size vs size on disk Have you ever noticed that your file explorer displays two different sizes for each file: size, and size on disk.

Size and Size on disk Why are size and size on disk slightly different? You can use the du command on Linux to see it yourself. What is disk fragmentation? Over time, new files are written to the disk, existing files get bigger, shrunk, or deleted. That's when new files need to be stored as fragments.

An example of a fragmented and non-fragmented file Let's make it more clear with an example. Imagine you have a Word document named myfile. This overhead applies to saving the file back to the disk as well. Fragmentation is one of the reasons some operating systems get slow as the file system ages. Should We Care About Fragmentation these days?

The short answer is: not anymore! Additionally, ext4 uses an allocation technique called delayed allocation. Delayed allocation actively reduces fragmentation and increases performance.

Directories A Directory Folder in Windows is a special file used as a logical container to group files and directories within a file system. On Linux, you can use the ls in a directory to see the directory entries with their associated inode numbers: ls -lai And the output would be something like this: drwxr-xr-x 14 root root Dec 1 The key is to decide on a system, communicate it clearly to everyone in your organization, and be consistent. Set goals for digital file organization.

Organizing digital files can take over your life if you let it, so start by getting specific about what you want to accomplish. The office manager will start by spending one Friday afternoon on this, followed by an hour or so each week. Talk to the leadership team at your organization so you understand their priorities. If you have time, get input from everyone. Here are a few questions to start with:.

Organize digital files by name, date, project, or department. The best way to organize files on a computer will vary based on your organization and its needs. Decide whether it makes sense to organize files by name, date, project, or department. After that, shared drive folder structure best practice is to start with your broadest categories for your main folders, and then get more specific with subfolders. Pros: Names are less ambiguous than other categories, such as industry or product type.

Cons: It can be confusing if the client or company changes their name. It can be difficult to remember when you worked on a certain project at a glance. Best for: Organizations with large amounts of files tied to time periods, like a financial services business.

Best for: Organizations with lots of cross-departmental collaboration—for example, a project manager, writer, and graphic designer work together on every project. Cons: It can be hard to find related projects unless you include that in the file naming structure. Pros: Each team knows where to find their files, so searching is faster. Cons: When departments do collaborate, it can be confusing deciding where to save files.

Ideally, your file names should be detailed enough that you know exactly what they are at a glance. Start with the broadest category at the beginning of the file name, like the year or department, and then get more specific.

Whatever you decide, just be consistent. Work together with features like chat, file sharing, and video calling. Establish a system for version control. Another option is to establish a clear order of file name endings and ask the whole organization to stick to it. This is useful if you want a separate file to mark each stage of a process, but it does lead to more files. Meet Grammar Coach. How to use be like in a sentence. His strong legs and his broad, spade-like feet helped to make him a fine swimmer.

The wave-like movement of these animals is particularly graceful and cleverly done.