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Can someone explain to me use of MyDefrag flash script? I read the article on MyDefrag's site, but the concept is still unclear to me. What exactly is that extra processing needed?

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It tells you in the article:

Many people think that flash disks do not benefit from defragmentation and optimization because bandwidth and access time are the same for the entire disk, unlike mechanical harddisks which are faster at the beginning than the end. But fragmented files need extra processing time inside Windows, not noticeable on mechanical harddisks but very significant on fast flash memory disks. Even more important is free space optimization. Flash memory is written in large blocks, and if free space is fragmented then Windows has to (read and) write much more data than the size of the file. This takes time, which translates into lower speed.

So if you have a file which is made up of 4 small blocks of data of, say 1k each, each one in a different read/write block (let's call it a page) of, say, 128k in size, then 4 pages have to be transferred (totalling 512k) just to get the 4k of data out of it.

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Some information I had access to point that it is flash memory controller that does rearrangement with no intervention form windows. What does windows then do? – AndrejaKo Mar 20 '11 at 17:54
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What does windows do? Well, crash lots I guess. – Majenko Mar 20 '11 at 17:54
But seriously - the processing needs to be done - it doesn't matter whether it's Windows or the drive controller that does it. It all amounts to delays. – Majenko Mar 20 '11 at 17:55
I'm aware of that, but in case where the controller is a problem on SSDs there are ways to avoid the delays such as extra space allocated to the controller for file creation when the disk is full and so on. The windows point is what I'd like to focus on. – AndrejaKo Mar 20 '11 at 18:15
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