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That's practically a guaranteed way to produce more fragmented disk layouts. Well done, current MSFT programmers.

Is disk fragmentation a serious problem for you? I use SSDs for most of my drives, and let the Microsoft defragger do its thing once in a while, and leave it at that. Doesn't seem to bother me none.



You're not supposed to defrag an SSD with Microsoft defragger, are you really doing that?


Nope, sorry-- I wrote too quickly. What I meant to say was that I use an SSD on most drives, and run the Microsoft defragger periodically on the remainder.


In the case of Linux, more specifically ext4), you get some benefit from having the blocks of a given file contiguous, as they will end up being one single extent.


Do you have a reference for this info?


http://www.micro-isv.asia/2010/12/never-defragment-an-ssd/

"The key benefit to SSDs is that they have virtually no seek time. Reading adjacent blocks of data is no faster than reading blocks that are spread out over the drive. Fragmentation does not affect SSD drive speed.

(...) SSD drives physically wear out as you write to them. Defragmentation software moves around all the files on your drive. Thus, defragmenting an SSD reduces its life span without giving you any benefits."


I had an old netbook with an SSD. A lot of folk noticed that the performance of the disk got slower over time. Surprisingly, defragging the drive actually improved the performance -- but IIRC it was a side effect of the process, not directly anything to do with fragmentation.

I don't quite remember what the issue was, but there was a good anandtech article about it: http://www.anandtech.com/show/2738/8

Fairly certain modern SSDs are not affected, in any case.


Ahh, do you know why? TRIM support isn't being used.

When you're defragmenting, all you're doing is forcing the drive to write a lot, which itself essentially is a crazy way to fix it without TRIM command, but it works. On the other hand, you're doing a lot more write cycles than what TRIM or garbage collection would normally do.


Article says: (Windows 7) "the OS knows it’s a SSD and turns off features like defrag"

So you claim to see improvement from something turned off by the OS? How?


Err, this was several years ago, and I was relaying what other folk with the same device (ASUS 901) reported, not my personal experience.

(And not only was this was before the release of Windows 7, it actually came with some version of Xandros installed...)


SSDs don't benefit from data being sequentially aligned. Random access is just as fast. Also, you should minimize the write access to the disk whenever possible.




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