SATA2 VS Raptor VS RAID0

Kareem

I am thinking of changing my HDD setup. As you know HDD is the slowest thing in your PC. Solid-state drives are not available yet in Lebanon and too expensive.

The question is does it worth ? Performance wise I would like to know which is faster as a primariy/logical drive between :

1- 1TB SATA2 7200RPM 32MB cache
2- 2 x 1TB SATA2 7200RPM 32MB cache RAID 0
3- Western Digital Raptor 10,000RPM SATA

I read on different forums different results so any personal experience/comment would be appreciated.

BashLogic

raptor +raid0 is the fastest combination you can get, but i still would use raid1
if you really have the cash to waste, you can always go with scsi 15k rpm disks on raid1 ;)

if you want to stick with home pc stuff, get a real bootable sata raid card such as 3ware
and plug in 2 raptor disks.

if you want to further optimize, get another card and place it on a an unshared bus. then add another
pair of disks.

now since you have two raid cards with one sets of disks, you can configure your OS and applications to
use the second raid set to host the swap/cache files. and the first raidset to host the OS + appliction binaries.

for data you can a third card with 4 disks set to raid5

now you have a next to real multimedia rendering PC ;) the real thing would use SAN or scsi disks and lots of them ;)

Kareem

Yep but 150GB 10000RPM S-ATA Raptor is for 310$ vat included so i will need to pay around 620$ for Raptor with RAID0. I read that the new SATA 7200.11 is too close or even faster in some tests than the raptor.

Money/performance wise can you come up with a good combination ? Thanks.

BashLogic

yep, the raptors cost, you did not make it clear whether money was a question ;)
anyhow, raptor will always beat the sata due to two factors;
- the raptor capacirty set at 150gb tells you that it has less physical movement in comparison to 500gb or 1gb disks. what this means is that the needle head ont he disk disk platter has less movement hence is faster when performing I/O changes on the disk
- the 10k rpm speeds up the seek

in single large files, you might experience the sata to perform just as well or better but with average small files, the raptors will definetly beat the sata 7k rpm disks.

since you have not elaborated on what your aim is its hard to tell you what the possible best configuration is.

one thing is for sure, no matter what, DO NOT USE SOFTWARE/OS RAID NOR MOTHERBOARD INTEGRATED RAID STUFF!!!!!!!!! the best sata raid controllers that i have come are 3ware and some have been talking about promise, the lator i can not comment as its product line has totally changed since 10years ago the last time i used promise products.

but in short if you are working with linux, just get smaller disks for the os, lets say 80gb 7k/rpm sata2 disks
add another pair of disks of same specs for swap/cache. have both configured with software raid mdadm (comes with linux). lets presume you have a MB with 4-6 sata controllers. connect the disks 1-4 to the mb
and create the raid with mdadm raid in such a manner that disks 1 and 3 (each on a different controller plugs) and respectively 2-4.

when you look at the motherboard you often see that you have two parallel sata plugins and several of those depending onthe version of your motherboard. each pair often works thru its own bus and in more rare cases thru a separate asic. so when you greate a a raid from two disks with each disk from a different path on the motherboard, you are ensuring that there wont be a congestion and have more bus space for data transfer. if both of the raid1 disks were to be on the same bus behind the same controller, then you would have the I/O traffic for both of the disks travelling down the same path and consuming bandwidth transfer capacity.

now when you create two raidsets of raid1, you still might need a separate data storage device, for that you can use raid5.

my previous personal linux server was setup so that i had 2x 80gb pata disks as raid1 for os+swap (swap enabled without raid!!! where swap partition on each disk of the raidset was its own separate swap partition that was not mirrored!!! if you mirror swap you are congesting your performance!!!). in addition, i had 4x sata 160gb disks setup as raid5.so with this setup i did not face performance issues.

Kareem

BashLogic wroteone thing is for sure, no matter what, DO NOT USE SOFTWARE/OS RAID NOR MOTHERBOARD INTEGRATED RAID STUFF!!!!!!!!! the best sata raid controllers that i have come are 3ware and some have been talking about promise, the lator i can not comment as its product line has totally changed since 10years ago the last time i used promise products.

Actually are you saying I should not use my Asus P6T RAID controller thing ? ( sorry if I did not get you ).

Another question, I need to run RAID 0 because I will only install OS and softwares on it so I do not mind reinstalling everything if any of the drives fails. Cant I use SATA2 1.5TB as a storage and RAID 0 as logical drive ? Thanks for the help here but you know I spent too much time away from hardware things I feel myself completely lost.

BashLogic

yep, thats more or less what i said, i have had bad experiences with integrated features on motherboard regardless of vendor, model or version.

once again, i dont know what your performance requirements are and what your intentions are but the raid1 should suffice, raid0 is theoratically faster, i have never used raid0 but its claimed to be faster.

you will experience a bottleneck if your data is on a single 1.5tb disk. i would raid that as raid5 for data storage.

Kareem

Thanks BashLogic, that was enough for me ;)