RAID Noob Advice

[RichMcc]

Hi all

Im looking for advice for a new system build if you'll be so kind, Ive always been aware of raid but never used it before (never had the need).
But Im going to be building a high spec games/3d development rig shortly, I'll be using vista 64bit.
Now having used vista 32bit on my present machine since release Im increasingly aware of the slow disk access, endless chugging of the hard drives that vista seems to cause compared to XP. Also I want to speed up IO as much as possible so Im interested in performance over redundancy.

From what I understand RAID 1 seems like the one to go for in terms of best performance, is this correct?
But Raid 10 sounds ok (best of both 0 & 1) but does it slow things down?

Also Im guessing more disks = greater performance?
Is it ok to just use 2 drives or should I get 3?

Another question is can I use say two 500's in the array (for OS and apps) and add another internal drive later say a 1tb that isn't part of the array? Just for long term, low access storage for stuff I keep but dont access often?

Im going to be using this board which supports 0, 1, 5, 10 : -
P5E3 Premium/WiFi-AP @n
http://asus.com/products.aspx?l1=3&l2=11&l3=640&l4=0&model=2069&modelmenu=1

And at £61 bucks a pop this seems like the drive for me: -
Western Digital Caviar RE2 500GB 7200RPM S300 16MB RAID edition
http://www.dabs.com/productview.aspx?Quicklinx=4LFR

Advice would be greatly appriciated

 

[BigBurn]

From what I understand RAID 1 seems like the one to go for in terms of best performance, is this correct?

I am no RAID expert but RAID 0 is the performance one by splitting the file on all your hardrives, RAID 1 is the one that make a copy of the file on both your harddrive.

Another question is can I use say two 500's in the array (for OS and apps) and add another internal drive later say a 1tb that isn't part of the array? Just for long term, low access storage for stuff I keep but dont access often?

Yes

 

[RichMcc]

Interesting, my understanding was because the same data was mirrored on several drives and if your using a multithreaded OS it grabs data from which ever drive was under least load? or a bit from this drive, a bit from that drive and so on...
Unless Im totally wrong :S

 

[RichMcc]

Ahh actually your totally right I just read something that explained it in dummy terms. :lol:
However the loosing everything if one drive dies doesn't sound good, not that I would expect that to happen but its still a slight worry.

Ok new question, raid 10 vs 0?
I guess 10 gives me fault tollerence and some performance increase but at what cost? Im guessing its slower than 0?
Also is it worse to have more drives in a raid 0 setup?

 

[RichMcc]

Done a bit more reading!
I guess what I should do is get 3 drives and run them like this...

2x 500gb raid drives using RAID 0 for performance and just use them for OS and Apps (stuff that can be replaced in the event of a drive failing)

1x 500gb drive outside the array for documents, photo's etc etc so if the array did go down my stuffs still safe on that drive.

Sorted!

 

[vmardegan]

I believe that what you're looking for is RAID-0. This will enable simultaneous activity on both drives and the drive final capacity will be the sum of both drives.

RAID 1 you have more reliability on data. Drive 2 works as a mirror for Drive 1, so if something happens to one of each drive the system will keep running and the data will be safe on the remaining drive. However, the performance will be similar to a single drive and the final capacity is going to be the same as one single drive.

RAID 5 is "kind of" the best of both worlds. You will need three or more similar drives to run this array. The final capacity is going to be equal as the double of one drive, you will have "double drive" activity (increased performance) and the third drive works as "the backup". If something happens to one of the drives, the system keeps running and you can easily swap the broken drive without compromising the data integrity.

Raid 10 is the combination of RAID 0 and RAID 1 array. You will need 4 or more drives to run this set up. It's like running two arrays of RAID-0, where the second array is only the mirror of the first array. Final capacity will be equal as the double of one single drive.

There is also another array commonly known as JBOD (Just a Bunch of Disks). The principle here is to bundle all drive capacity in a single logic unit and it does not matter if the drives are different. Final capacity is going to be equal the sum of the capacity of all drives, but there is no performance increase neither "backup reliability".

My recommendation is to run either RAID-0 and have a external backup drive (or other regular/reliable alternative) or go all the way to RAID-5 (but still having some sort of backup in case you accidentally delete one file or have a virus attack). RAID 10 is too much expensive, since RAID-5 can almost deliver same performance and JBOD is just too risky and there is no performance improvement (neither "backup") in the end.

I hope this helps, and I also hope this whole thing is right. Sorry if there is any mistake somewhere, but this is what I know so far about most common used RAID arrays.

 

[1haplo]

I love muy RAID0. I can say that I will no go back to a single drive system unless something bad happens.

Toms did a RAID scaling artical. Here is the link
http://www.tomshardware.com/reviews/RAID-SCALING-CHARTS,1635.html

1Haplo

 

[RichMcc]

No thats absolutly brilliant, well done! Best explenation Ive found and Ive been looking for an hour or two...

I'll go for RAID 0 for the first two drives (OS etc) for performance and have a 3rd to keep work stuff on.

RAID 5 sounds... good on paper but I dont think its for me, I knew JBOD was a bit pants to begin with

Thanks again