This is one of those questions that gets my most common and my most favorite answer: “It depends.”
It depends on the drive. It depends on your computer. It depends on how you use your computer.
So, how can we narrow this down?
Become a Patron of Ask Leo! and go ad-free!
Defragging your C: drive
Frankly, defragging any drive other than the system drive (i.e. your C: drive) is typically not important. It’s probably not something that you’ll want to do often.
Why? The C: drive usually does the most work. That’s where Windows picks up its files from; it’s where all of your programs are installed; it’s where Windows is reading and writing to the registry.
You definitely want to make sure that the C: drive is defragged regularly. Personally, I kind of like the settings in Windows 7 to defrag all of the drives that are installed on the system once a week.
Other drives
When it comes to other drives, like your D: drive or even external drives (if you’ve got them), it gets a little weirder.
If the drives are used really lightly, I don’t think you’ll find that defragging is really going to buy you that much. It certainly doesn’t hurt to do it, other than the time it takes, but defragging a lightly used drive is just not going to have that much performance impact. And that’s really all that defragging is about – improving performance and making the disk access faster.
When to defrag other drives
However, if you are doing things with your other drives like moving your paging file, storing your temporary files, or reading and writing documents or to a stored database, then defragging could make a lot of sense. You should probably defrag on the same once-a-week schedule with your C: drive.
In either case, there’s no harm in defragging your D: drive. In fact, if you’re running Windows 7 and the automatic defrag is set to happen, chances are your D: drive is already being defragged along with the C once a week.
Exception to the rule
Now, the other exception is if the drive is a Solid State Drive or a USB flash drive. In either of those kinds of memory-based storage technologies, you don’t want to defrag at all.
Why? Well, you’re not going to get much if any of a performance boost (there’s some controversy around this, but supposedly defragging these drives is just not worth it).
Because defragging reads, and particularly writes, so much to the drive, it will actually cause the SSD or USB flash drive to wear out much faster.
So, in short, if you have a heavily used drive, make sure that it’s getting defragged on a regular basis. If it’s not getting used that heavily and it’s idle most of the time, there’s no harm in defragging it, but I wouldn’t take any additional steps or go out of my way to make sure that it was being defragged on any kind of a regular basis.
Shall I use your defrag. advice for Win. 7; and apply it to my Vista machine? All disks are on a regular schedule here; but I wondered if I should change my settings for just the C: drive most of the time. The only thing on my D: drive is my Vista OS. Evidently, it has not been defraging regularly as per the scheduling because it has been running for hours now since I manually prompted it to run all disks.
Hello Leo,
Thank you very for these statements. They bring peace of mind.
“In either case, there’s no harm in defragging your D: drive.”
“You definitely want to make sure that the C: drive is defragged regularly.”
However, I still have one more question. My D: drive is the recovery drive, is this statement still valid for defragging the recovery drive? – “…there’s no harm in defragging your D: drive.”
I look forward to your reply.
Thanks,
Temitope
Yep. There’s no harm. Not much point, but no harm.