why is defragging not really a thing anymore?

Question

I was born in 1973, got my first computer in 1994, defragging was part of regular maintenance. I can’t remember the last time I defragged anything, even though I have several devices with hard drives, including a Windows laptop. Has storage technology changed so much that defragging isn’t necessary anymore? Is it even possible to defrag a smart phone hard drive?

edit to add: I apologize for posting this same question several times, I was getting an error message every time I hit “post”… but from looking around, it seems I’m not the only one having this problem today.

In: 821

Answer 1

With hard drives, this is still necessary if you’re using a filesystem such as NTFS or FAT32, both of which become fragmented easily and still need to be regularly degragmented. Some filesystems (such as Mac OS HFS+ or Linux EXT4) don’t become fragmented easily because the operating system will physically move files on the disk as data is written to ensure that they don’t become fragmented to begin with. These filesystems rarely require defragmentation as a result. *(Technically, it is still possible for EXT4 or HFS+ filesystems to become fragmented in some very specific circumstances, namely when the disk is almost completely full, but this is rare.)*

With SSDs, it’s a totally different story and defragmentation is actually detrimental. Not only do they lack moving parts (and therefore aren’t bogged down by fragmentation), but the SSD controller itself purposefully fragments the data as a part of its wear leveling algorithms anyway. This happens invisibly to the OS and it takes place at the physical hardware level. Even if you were to defragment it by the operating system, the physical flash itself would still scatter all of the data throughout the disk to make sure that all of the blocks are wearing evenly, even if it “reports to the OS” that the data isn’t fragmented.

For this reason, defragmenting SSDs has no benefit on any filesystem. It doesn’t actually ensure that the physical data is less fragmented (it still will be fragmented by the wear leveling controller on the physical flash anyway). It just fools the OS into *thinking* that it’s not fragmented, which has no real benefit and just adds additional wear and tear to the SSD.

Answer 2

With hard drives, this is still necessary if you’re using a filesystem such as NTFS or FAT32, both of which become fragmented easily and still need to be regularly degragmented. Some filesystems (such as Mac OS HFS+ or Linux EXT4) don’t become fragmented easily because the operating system will physically move files on the disk as data is written to ensure that they don’t become fragmented to begin with. These filesystems rarely require defragmentation as a result. *(Technically, it is still possible for EXT4 or HFS+ filesystems to become fragmented in some very specific circumstances, namely when the disk is almost completely full, but this is rare.)*

With SSDs, it’s a totally different story and defragmentation is actually detrimental. Not only do they lack moving parts (and therefore aren’t bogged down by fragmentation), but the SSD controller itself purposefully fragments the data as a part of its wear leveling algorithms anyway. This happens invisibly to the OS and it takes place at the physical hardware level. Even if you were to defragment it by the operating system, the physical flash itself would still scatter all of the data throughout the disk to make sure that all of the blocks are wearing evenly, even if it “reports to the OS” that the data isn’t fragmented.

For this reason, defragmenting SSDs has no benefit on any filesystem. It doesn’t actually ensure that the physical data is less fragmented (it still will be fragmented by the wear leveling controller on the physical flash anyway). It just fools the OS into *thinking* that it’s not fragmented, which has no real benefit and just adds additional wear and tear to the SSD.