If you’ve ever owned a traditional hard disk drive (HDD), then you've probably defragged it at some stage. This is because defragging an HDD is necessary due to the way it's built.
In a spinning hard drive, data is laid down in a continuous line as the disk spins. When the data is read again, the drive head (the part that moves over the surface of the disk) can track this line of data making retrieval simple and efficient. Over time, as the drive fills up and data is moved or deleted, there is less space available for continuous tracks of data, so the data gets stored where there is room. This can cause the blocks of data to fragment as they are scattered in pieces around the drive. Reading the drive now means the drive head must search across the disk’s surface for the data it needs. This is a much slower process.
Defragging re-arranges large files so they are stored in one continuous area of a hard disk drive (HDD). This means that the file can be read in one go, which is faster.
HDDs are mechanical drives, with a relatively long seek time of approximately 15 milliseconds (ms), so every time a file is fragmented you lose 15ms finding the next one. That’s not much for one file, but it really adds up when reading lots of different files split into lots of different fragments. In recent years, many people have been replacing their HDDs with SSDs due to the improvements in size, weight, speed, and power efficiency they bring. Those of us used to defragging our hard disk drives may wonder if it is necessary to defrag an SSD. We answer that question below.
The short answer is no: you don't need to defrag an SSD.
SSDs are designed to access file fragments without delay using flash memory, with an average seek time in the region of 0.1ms. So, you won’t really notice the benefit of defragged files — which means there is no performance advantage to defragging an SSD.
And, since SSDs often move data to temporary positions as part of its normal operation, defragging will actually take up more of your solid-state drive's limited rewrite capability.
Early models of SSD still suffered from issues of garbage data, however a new technique known as Trim was developed to counter this and prevent premature wear and tear on the drive. TRIM is present on all Crucial SATA and NVMe SSDs.
Defragmenting is not recommended for solid-state drives.
At best, it won't do anything to help get a faster SSD drive, at worst, it will use up write cycles.
If you have already defragged your SSD a few times, it won’t harm your SSD. However, it’s not a practice you should continue.
There are other ways to clean up and increase speed on your computer. There are even reasons for formatting an SSD, encrypting SSDs, and ways to increase storage space on an SSD. They all serve a purpose — there just isn’t a reason to defrag an SSD.
If speed and performance of your current drive is a problem, consider upgrading to a new SSD, and use the Crucial System Scanner to guarantee compatibility with your computer. There are two types of consumer SSDs: SATA and NVMe. Not all SSDs are compatible with every computer, so it’s important to know the type, form factor, and interface of any drive you may buy.
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