4x RAID-5 Raptors, faster or slower than single raptor?

[Nedkt]

Ok, I am using a single raptor for day-to-day things from the OS, to data, to work, to games, to everything else. If I went to a raid 5 array of 4 or 6 74 gig raptors with a 128 meg areca RAID controller, would this array be slower, faster or about the same speed as the single raptor? If about the same speed, about the same little slower or little faster?

Or is RAID 1 faster for day to day use than RAID 5? $-per-gig of storage aren't too much the issue.

 

[cs120ban]

if you run in RAID 10, it'll be faster than RAID 5.

This is how I have my servers setup. Redundancy is important.

OS raid 1 WD raptors
DATA raid 10 WD RE2

Else I'll go with
OS raid 0
DATA raid 10

 

[Flakes]

ditto on the raid 5 of 4 320 seagates(7200.10) drives, i should of got all of my drives today but theres been a delay in my order , hopefully ill get them tomorrow and have Raid 5 set up by the end of the week.

 

[clue69less]

if you run in RAID 10, it'll be faster than RAID 5.

Right. RAID10 is very competitive with RAID0 in fact, except WRT cost. RAID0 gives you all of your drives combined capacities, RAID10 gives half and requires at least 4 drives. Still, it is a setup that makes great sense if considering a RAID5. Wusy's recommendation of having the OS on a single Raptor is right on too.

 

[lrai]

The main purpose of RAID5 is really to have redundancy with minimal capacity loss, nothing to do with speed.

I totally disagree. RAID 5 is significally faster than single drive even in software RAID.
He is planning to use an ARECA hardware raid adaptor with 128 M cache.
Look at the specs of this beauty: Here

For RAID 0 :
Sustained Rate: Read 885 Write 847
All-in-Cache: Read 1624 Write 1295

For RAID 5 :
Sustained Rate: Read 846 Write 816
All-in-Cache: Read 1624 Write 1295

The real speed depends on the drives I know but the card has the horsepower to do all the RAID 5 XOR-ing at almost the same speed as RAID 0.

Here are 2 actual benchmarks of the card with 4 Raptors:

http://www.planetamd64.com/index.php?act=Attach&type=post&id=3781
http://www.planetamd64.com/index.php?act=Attach&type=post&id=3780

 

[Flakes]

torrents suck i use newsgroups, much faster.

now back on topic, raid 5 will give you redundency and similar speeds to raid0 in other words you probably wont notice the difference in speed between raid0 and 5, personnally im going raid 5 for the speed and the fact i will have a total of 960GB to play with once initialized(you lose one drive in raid5)

 

[gentrinity]

Im considering getting into a multiple array but Im not sure if what I want to do is possible.

Obviously, RAID 5 is not for me since I am looking for performance. I plan on building a video editing workstation.

So heres what I would like to do;

I want to get 2 Raptors 150GB in RAID 0, which I will use for OS and rendering, If I need extra space for my renders, Ill consider adding a third disk to the arrays, 450GB should be enough for HD, as long as its one file at a time.

I then plan on having a backup HD which I will use to keep all the important stuff, so if my RAID 0 dies, it wont matter cause I will try and keep it as cleen as possible to help keep performance maxed out.

The trick is to get the Backup HDs into a seperate RAID 1 config. I would then buy two Caviars 500GB, or I could set up a RAID 5 with 3 Caviars 500GB, which if im not mistaken will give me 1TB and any drive can die before I loose the array, so its pretty decent fault tolerance. Since I will be doing mostly reads from the backup, then I dont mind the slow write performance compared to a RAID 1.

The thing about this is that I want two basically have two seperate arrays that dont do anything together, its one HD for a RAID 0 and seperate RAID 1 or 5 that acts alone.

From what I have read, you can add arrays, but they work together, I want to know if I can get two completely seperate arrays for two HDs, one that for OS in RAID 0, one for backup/storage in RAID 1 or 5.'

THANKS FOR THE HELP!!!!

 

[gentrinity]

sweetness

I saw some benchmarks and read a review about Matrix RAID, and that its actually just as good as regular RAID, with less expense. Ill look into that then, thanks for the reply. Sorry about my redundancy, I have a video project that needs to be previewed in a few hours and ive been having non stop trouble capturing the video, didnt realize how I was writing.