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Defragmentation: Key operating system considerations 

If your computer’s running slower than usual, defragging it can often help put some zip back into it. Read on to learn when is best to do this and how to defrag your device. You’ll also discover how Avira Free Security can help you tune up and rev up your computer.


What do the terms fragmentation and defragmentation mean? 

One of the main possible culprits causing your computer to gradually crawl along is a fragmented hard drive. This means that pieces of files have been stored on the hard drive in different partitions — or, in tech terms, logically separated parts of a hard drive. This can happen over time if you change or delete files, creating gaps on the hard drive. 

New files are then saved automatically in the resulting gaps. If the gaps are too large for the new files, they are split across several gaps — resulting in a fragmented file. This isn’t a bad thing in itself, but it can slow down your device. That’s because if you open a fragmented file, the computer has to read it from different locations on the hard drive to display its contents. The same applies to programs, which can also lead to 100% disk usage, slamming the brakes on your device’s performance. 

You can piece together those fragmented files by defragmenting your computer. Your computer will then rearrange the files and programs on the hard drive so that all the fragments sit one after the other. This allows the computer to access the file or program more quickly. It also saves your hard drive from having to spin up and go hunting for file fragments, and can increase its lifespan. You can also use the CHCKDSK command to scan and repair your Windows hard drive.  

Defragmentation vs consolidation: What’s the difference? 

If a single file has been fragmented, the pieces are brought together again with a consolidation. This usually happens automatically as part of a disk defragmentation, where the file fragments are rearranged so they sit one after the other. This allows the computer to read and open the file faster. The processes of consolidation and defragmentation usually go hand in hand.  

Here’s how to defrag your files depending on your operating system 

The latest operating systems usually defragment your drive automatically on a regular basis. But if you still notice your PC is becoming significantly slower, you can also start the process manually. Let’s take a look at how you do this on different operating systems — from Windows to iOS. 

By the way: If your PC is crawling along, it can also be a sign that it’s infected with computer viruses or other malware. This makes it a good idea to protect your device with an antivirus solution and scan it to rule out an infection as the root cause for your slow computer. Avira Free Security includes real-time virus protection thanks to cloud-based detection of the latest threats, making it safer to surf the internet on your PC. 


From Windows 8 to 11: Here’s your step-by-step guide to defragmenting your drive 

If your computer has Windows 8 or newer, follow these steps when defragmenting your drive to rev up your increasingly slower computer: 

  • Open the Start menu: Click the Windows icon in the taskbar to open the Start menu. 
  • Enter this command: In the search bar, enter the command defrag and click the result Defragment and Optimize Drives. A window will then open showing all connected drives on your computer.
    The command defrag is entered in the search bar of the Windows Start menu. 
  • Analyze drives: Click Analyze to see which drive needs to be defragmented. 
  • Start defragmentation: To begin defragmentation, click Optimize.
    In the connected drives window, the respective drive can be selected and optimized. 
  • Turn on automatic defragmentation: If automatic defragmentation is turned off, you can turn it on if necessary. This saves you repeating the process manually again. 

By the way: The steps are almost identical to defragment a Windows 7 PC. You enter the command defrag in the Start menu, select Defragmentation from the results, and then click the desired disk. 

If you have a lot of files and your device hasn’t been defragmented in a long while, the process may take several hours. Unlike Windows 8 and newer versions, you can’t auto-defragment your hard drive with Windows 7. As such, always leave your PC to get on with the job of defragmenting your drive and never interrupt the process. 

Defragmenting a Mac: Do I even need to do that? 

In general, you don’t need to defragment a Mac. That’s because models with the OS X and macOS operating systems have built-in utilities that clean up a fragmented hard drive automatically. This makes manual defragmentation totally unnecessary. On top of that, most macOS versions don’t even support third-party software solutions that sort file fragments. That said, you can use apps to defragment older Mac devices — although, because the models are outdated, most tools are incompatible. 

Mobile devices: Do I need to defragment mine? 

As a rule, you don’t need to defrag your smartphone or tablet. That’s because the latest devices optimize their storage space automatically. In addition, most models these days have SSD storage. Never defragment such a drive as it shortens its lifespan. However, special apps can help optimize your mobile device’s storage space. 

Why is it harmful to defragment an SSD? 

Compared to traditional hard drives, SSDs (solid state disks) are significantly faster. One of the reasons for this is that they don’t have any mechanical moving parts — there’s no rotating disk nor is there a moving read head that controls the file fragments. Instead, the SSD controller can address the file components directly. Basically, this means that all memory cells are reached at the same speed. This allows the computer to access file parts directly — no matter where they are on the SSD. 

You don’t need to defrag an SSD — and it can even harm the drive. This is because the memory cells of an SSD have a limited lifespan and stop working after a certain number of write accesses. However, with normal use, this number is rarely reached in practice because the controllers distribute the stored data evenly across the SSD. If an operating system or an external program intervenes in this process and defragments the SSD, this shortens its lifespan. Instead, you should use special programs to trim it — where the operating system informs the SSD which blocks of data are no longer considered in use so they can be erased. 

Are defragmentation programs worth it? 

In addition to defragging performed by the operating system, there are also programs that trigger this process. From simple software that defragments the hard drive to variants that can also optimize individual apps and trim SSDs, there’s a huge selection out there. The advantage of using optimization tools is that they contain numerous features, putting them in a different league to your operating system’s standard offering. 

An operating system’s own solutions usually still work reliably, but they’re often limited to partitions and don’t defragment individual files. Whether you choose a special program depends on your requirements. For everyday needs, (automatic) defragmentation by the operating system is usually sufficient. 

How to fix issues during the optimization process 

You may run into a range of difficulties during a planned defragmentation. Here are some of the most common issues and their solutions: 

  • Windows defragmentation won’t start: Background programs may be interfering with the hard drive defragmentation process. If Windows defragmentation doesn’t start, temporarily deactivate apps and programs running in the background. To do this, open the Task Manager and right-click to close any programs. Alternatively, you can use a special defragmentation program. 
  • Another program is defragmenting your drive: Want to defragment your hard drive manually but get the error message Disk Defragmenter was scheduled using another program? Then it’s probably because another application on your device is already planning or executing the process. The easiest thing to do is to end the program in question and delete its schedule in the Task Manager. The operating system should then be able to defrag your drive itself. 
  • Less storage space available: You may find after defragmenting your drive that you have less disk space available. This is because fragmented files are moved around during defragmentation. To accommodate these files, the system reserves space for this, meaning that less storage space is displayed temporarily. Once defragmentation is complete, restart your PC — you may even need to do that two or three times. The reserved storage space should then be available again. 

Third-party solutions can boost device performance 

With the latest devices, you typically don’t need to manually defragment them on a regular basis as they do this automatically. In the case of SSDs, never attempt to defragment them as this can significantly reduce their lifespan. Still want to give your computer a boost, such as to make games run faster? Then third-party solutions may be the right choice for you. 

Avira Free Security helps speed up processes on your computer. It also frees up space by removing junk and duplicate files. Our solution also helps you clean your entire system and prevent overheating, for greater stability and more responsiveness. You can also use the tool to delete personal data from your device’s cache — boosting your privacy in the process. 


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