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View Full Version : Why hards drives slow down when more full?


Destroy
02-18-10, 11:13 PM
I've noticed hard drives get slower and slower as they fill up.

Is it the fact that as it fills up, it uses the fastest part of the drive first?

CaptNKILL
02-18-10, 11:18 PM
Is it the fact that as it fills up, it uses the fastest part of the drive first?

Exactly. :)

Bman212121
02-19-10, 07:21 AM
Here is a good visual of that. A hard drive starts writing data on the very outer edge of the platter. This area of the drive is faster because more data passes under the read/write head in the same amount of time as it would on the inner most tracks. Data density is the same across the platter, but on the inside of the drive the circumference might only be 2" to make 1 rpm, where the outside has to cover 5" (theoretical numbers) in the same amount of time. that would mean that 2 1/2 times the amount of information can be read in the same amount of time.

http://img122.imageshack.us/img122/1439/drives2lr3.jpg

Destroy
02-19-10, 09:33 AM
So a good rule of thumb would be to use no more than 1/2 the hard drive for continued snappy performance?

ViN86
02-19-10, 10:34 AM
Well the more files you have the longer it takes the drive to find the file you want. Think about when you sort through things. The more things you have to sort through the longer it takes.

ViN86
02-19-10, 10:39 AM
So a good rule of thumb would be to use no more than 1/2 the hard drive for continued snappy performance?

I think they have software that will optimize your drives and move the most accessed files closer together for fast finding.

nekrosoft13
02-19-10, 10:53 AM
I think they have software that will optimize your drives and move the most accessed files closer together for fast finding.

its called defrag program, not every program has that function.

O&O Defrag does. the latest version has even better system, when you do full defrag, on C drive it seperates important files (windows directory, program files etc.., system files) it put these in the begining of the drive.

other stuff like: installer directory, my documents, pictures, music etc... dumps them in the back

Bman212121
02-19-10, 05:42 PM
So a good rule of thumb would be to use no more than 1/2 the hard drive for continued snappy performance?

Pcper did an article a month or so ago about only using part of your drive. I've done it for a while now where I'll take 2 drives, Raid 0, then only partition the first couple hundred GB. In theory it should maintain better performance that way because files will only reside on the fastest part of the drive, and seek time should be decreased because the heads have less distance to travel.

Like Vin said, you can really slow down the computer with a lot of little files. Everything will get fragmented, and the MFT will grow large trying to index all of the files. The less stuff on the drive the better it should perform.

Destroy
02-20-10, 08:42 AM
Pcper did an article a month or so ago about only using part of your drive. I've done it for a while now where I'll take 2 drives, Raid 0, then only partition the first couple hundred GB. In theory it should maintain better performance that way because files will only reside on the fastest part of the drive, and seek time should be decreased because the heads have less distance to travel.

Like Vin said, you can really slow down the computer with a lot of little files. Everything will get fragmented, and the MFT will grow large trying to index all of the files. The less stuff on the drive the better it should perform.

Makes sense but couldn't you partition it like you state and use the first 100Gigs for the OS and use the remaining partition of the HD for data/storage? Or will the fact that you have data AT ALL in the slower 2nd partition area cause the first partition to slow down?

logan
02-20-10, 10:07 AM
You could partition, but I think that'll be problematic for hardware/fake (bios) raid because they use the whole disk. My 3ware controller at home is all or nothing with my 4*1TB Blacks, same for my Windows machine using Intel's Matrix Raid (ich9r). I saw an article several months ago about using SeaTools to set the size of a 1.5TB Seagate drive to 300GB (or something like that) as some type of alternative to a WD Raptor. I think this (http://www.techwarelabs.com/seagate_1-5tb-mod/) was the original article, if not it may link there.

With software (md) raid on Linux, you can use partitions instead of entire disks. My server at work has 4*500GB with the OS on a 20GB mirror with 2 hot spares (same setup for /var and swap too) and then the leftover space is a 800gb raid10.