wow, I had no idea that so many people have absolutely no clue as to what "defraging a hard drive" does.
Defragging reorders blocks of files on a volume so that they're next to each other. This speeds reads.
Congratulations, I hire workers like you.
Sorry, I don't work for jackasses.
Dozens of TBs on Raids - Woooo. Was that meant to impress? I have a couple 3 TB Raids in my house alone. Now if you tried bragging with Petabytes or even a single Exabyte I might be impressed.
How do you think you get to Petabytes? 1 giant RAID? When I say "RAIDs", I mean hundreds of individual RAIDs set up across different sites. If you want me to make it simple for you, yes, I manage "Petabytes" distributed across 9 worldwide sites, mostly with active-active clusters connected to them. The Petabytes are broken down into 72 TB RAIDs (the limit on the EVAs we're working on). Happy?
Files are not always placed in a contiguous space. Slots like you described are filled with partial files. So pieces of one file may be located in several places, all tracked by a file table. Sure it runs slightly slower, depending on the level of fragmentation and what you are doing.
If you read my later reply you would've noticed I said exactly that.
In regards to my first reply, I left out something:
"In most modern filesystems
running embedded OSes, that 2 MB will sit there, waiting to be filled up by a really small file. If you never add a small file again, that's wasted space."
Most embedded OSes don't bother to fragment files across volumes. It can waste unnecessary power and CPU cycles that are better spent on, oh, I don't know -- managing the OS and playing media files.
As far as the iPod, that it makes no effort to defrag the drive seems obvious, but yes, wiping it and reloading it would defrag it. That it might be worth the time and effort and have any noticeable effect is probably marginal.
If you're talking about an iPod Nano with 4 GB of music, yes, defragging would be of little benefit. If you're talking about a 60 GB iPod with massive video files, assuming the files are broken into chunks and spread across the volume, you're talking about potentially unnecessary reads as it bounces around the disk. That means power wasted, among other things. To say that defragging the iPod isn't a worthwhile question to ask is stupid.
Finally, may I make a suggestion (assuming you do "hire people"): belittling people's expertise when you yourself know next to nothing about the topic only makes you look foolish. Picking apart a single sentence on a message board forum only makes you look like the Comic Book Guy. May I suggest next time *contributing to the discussion civilly*. I know that's something they didn't teach you at MBA school, but it's high time you learned it.
