Why don’t you have to defrag an iPad or iPhone?
Asked by
2davidc8 (
10189
)
August 18th, 2013
I took this question to my local Apple store, but the “geniuses” there had no idea what “defragging” was. So, I guess you don’t have to defrag these devices.
My question is, why not? After all, I’m constantly loading and deleting stuff onto/from these devices.
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9 Answers
Do you have to defragment any other smartphone or tablet? I never have. The only thing I’ve ever defragmented is my PC.
No Apple products made recently require defragmentation; not even their computers. Any OS X later than 10.2 doesn’t need it because “OS X has its own built-in safeguards that prevent files from becoming fragmented in the first place.”
Defragging is useful on a hard drive, where a read head physically moves to and fro. Defragging reduces the necessary movement.
On a solid state drive, there is no movement. Defragging is not necessary and has no (or extremely little) benefit.
Modern operating systems are made to prevent fragmentation on hard drives so defragging isn’t necessary.
The iPhone software is itself a derivative of OS X (Apple’s software for laptop/desktop machines) and OS X is a direct derivative of Unix (not Linux).
Unix has always been SUBSTANTIALLY better about managing fragmentation, since the beginning of Unix 35 years ago. Microsoft OS software, on the other hand, has been horrible at disk management and fragmentation; specifically NTFS – the current disk management structure – is lousy.
iOS doesn’t have defrag because, frankly, it doesn’t need it.
I remember reading the code that does on-the-fly defragmentation. A lot of the underlying code in OS X is open source. IIRC any file over 20 MB is saved to a contiguous part of the drive when it is saved. Even if it needs to move a few things around first.
Defragging an SSD or similar storage device is unnecessary and actually undesirable.
Unnecessary because the seek times are fast enough that there is no performance benefit.
Undesirable because they have a limited number of read/write cycles. While that number has come up a few orders of magnitude over the years to where defragging will no longer cut the device’s lifespan to under a year, the simple fact remains that putting extra wear on something for no good reason (no gain in performance) is just silly, stupid, and wrong.
OS X is not immune to fragmentation, but HFS+ is optimized so that the effect it has is minimal. The only way to be immune is to have flash or solid state memory in your device.
Ah, I see. Thanks for the explanations, everyone!
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