Platters, capacity and speed drop off...

[killtacular]

Hello my lovelies!

At this moment in time, I have a 250GB Hard drive and I have noticed that nearing the end of storage capacity has caused my hard drive to slow down, as it the speed has dropped off...Is this because the read / write heads have to move to different platters near to the end of the drive?

Let me put it this way, the Samsung F1 1TB has 3 x 334GB platters. If I purchased it, and transferred everything over from my current drive, only 200GB of platter number one will be used, correct? If so, there will not be any speed drop off as only platter one access is needed and so he read / write heads don't need to move to the other platters, which would cause speed issues, right?

Thanks for any info on this topic.

 

[royalcrown]

No, drives write evenly between the platters from outside to in adaik, your speed drop off is due to the fact that the inner diameter of the platters has a smaller circumference and in effect, moves "slower"

pot a penny on an lp, the closer you get to the outside, the greater chance it will fly off because the outside is moving "faster". same here

 

[killtacular]

pot a penny on an lp, the closer you get to the outside, the greater chance it will fly off because the outside is moving "faster". same here

Cheers Royal Crown, makes sense writing from outside to in, but I don't get your last sentence, having trouble deciphering it!

 

[royalcrown]

as your r/w head is on the outside, more platter travels underit per second at the same rpm, a sit moves from outside to in...less platter travels under the head and it slows down (the transfer rate).

What i mean is that if you draw a line from the inside to outside, like a spoke, the outside travels farther during one revolution then an area near the center by the time that line makes that revolution.

 

[royalcrown]

the formula is pi x the diameter...so say you have a 3.5 inch platter.

If it is 2 inches from the center that is 2 x 3.14 so the head travels over 6.18 inches of platter per rev. at the outside of 3.5 inches (3.5 x 3.14), the head travels over 10.99 inches during 1 revolution.

 

[mathiasschnell]

(Center of platter) O----------------------------------) (Edge of platter)
Slower ---------------- Faster

There.

 

[storageinventor]

Although the innermost cylinders have fewer blocks in them than the outer cylinders, if you are noticing a significant reduction in performance as your disk nears the full point, it probably has more to to with disk fragmentation than anything else.

Depending on the file system you use, the file system may try to keep each file from being fragmented by allocating space for the file where it will fit best. As you delete files and create new ones, the free blocks become more and more scattered. As the file system volume begins to reach the full point, it runs out of large runs of free blocks. If you try to store a large file, it must do so by allocating lots of free blocks scattered throughout the volume.

It nearly always takes a lot more time to read or write a fragmented file than one that is not fragmented.

 

[royalcrown]

storageinventor...that is true block wise, but don't forget that aerial density is constant across the surface..what we really need square platters...lol.

 

[killtacular]

So, is it best to say that if I went for a 1TB drive, as I am only using 200GB of space at the moment, it would take far longer for me to get to the centre of the platter and so, would not experience a speed decrease so soon?

 

[cjl]

Yes, but likely the speed decrease was not from that anyways. As has been said, likely a speed decrease was due to increased fragmentation with less and less free space. This would improve too with a big drive though.

 

[assasin32]

My vote goes towards the fragmentation being the main problem, with you nearing the end of the HD platter as just a nicely added bounus you have. Thats what made 200gig HD grind down to halt recently because I ran out of space. Though it's a lot better since I cleared off a little bit of space (10gigs free now) and managed to defrag the whole thing, and im now using Diskeeper 2008 to keep it defraged in the backround so it's definately a lot snappier like it used to be, but not completely.

So with any luck the drive was just heavily fragmented and defragging it will help out quite a bit, but even if it does it will still be a bit slow as others have pointed out as it's nearing the center of the platter.

 

[killtacular]

Cool. I did recently defrag but I am sure it did not entirely do it.

I am in the process of d/l Diskeeper 2008 via you know what, LOL, and I will give that a go!

Thanks all, I love you all!

 

[assasin32]

Just be sure not to use I-Faast on there from my experience it was not worth it since I was nearing the end of my hard drive capacity, it in fact made things worst by keeping it fragmented, since it was trying to sort it by my needs. Than again I only had it on for a day or 2 so give it a shot if you want to.