Looking for cool things that I want (and can't possibly afford), I came across this puppy
A PCI Ramdrive. It operates at 133MB's and looks like a regular Drive to the PC. These things can be stacked up to as many PCI Slots as you have in your machine. I would love to run and OS off of this thing, as there is no defragging, and it is much faster as such. Also, the page file won't slow this down as it is running at the highest possibly speed that it can go. if this could go into an OS X machine, i imagine RAIDing the cards for superfast performance
Fragmentation is not a hard drive-only problem...any rewritable media can become fragmented, including flash memory. Fragmentation is simply when a file gets split into two or more pieces and those pieces are placed at different locations on the media. A "PCI RAMdrive" will become just as fragmented as a hard drive.
It won't be as big a problem as with mechanically read drives. Usually the problem with fragmentation on HDD's, is that the head swings like crazy to pick up the data on one end of the disk to another. Even though the data get's fragmented on memory, it would not be too much of a bottleneck, and the controller on the board should take care of that.
SInce there is nothing mechanical about memory (Unless it is drum ^_^) it doesn't take forever to access it. It may take 1ns to find out where it is an read it. Taking this data from the memory used as computer ram, it may get fragmented in the ram on my ibook, but I won't notice it slow down as the controller will keep track of where it is at.
Also, Ram is most likely capable reaching it's ceiling limit more than an HD, because of the direct access of the memory, versus the having to go thru controller chips to transfer the stuff down an 80-wire cable (U-ATA/EIDE) and make sure it gets there at the same time.
Too bad on the price of this though....
Do you think anyone could build one of these for cheaper? It would be cool using PC-3700 on a PCI-Express card in a PowerMac G5 and use it to boot from. Maybe for working with video and music.
That has nothing to do with fragmentation. The HDD knows exactly where every bit of data is located because of the file system index. A hard drive that randomly throws data about the platter is a piece of garbage and would never make it past quality control at a HDD manufacturer.
Fragmentation, as I said, is a result of the OS trying to put a square peg in a round hole. Think of fragmentation this way: You have a 500KB file. When saving this file, the OS sees that the first available spot on the disk is 250KB big. So it says, "OK, I'll put the first 250KB of the file there, then I'll put the rest in the next available spot." So you have your 500KB file split in two, and if you want to load the entire file later on, the disk needs to go to two different places to get all the data -- that's where the slowdown comes from. Now multiply that a few thousand times (the averge amount of fragmentation on a disk that's been used for several months) and there's a significant slowdown.
It doesn't matter what kind of disk the data is written to. Any kind of medium that can be written and rewritten on the fly is susceptable to fragmentation.
http://www.theregister.co.uk/2005/10/03/gigabyte_i-ram_ramdisk/
Gigabyte is going to, or already has, released a product such as this. Except it has a battery pack to keep what you store on the ramdisk active even after you shutdown the machine or remove the power. Plus, it doesn't require any special drivers as its goes through SATA. I remember hearing about this a while back when they announced it. Quite a neat concept, nothing new, but neat.