RAID 0 + Disk or RAID 5

D

djBon2112

Supreme [H]ardness
Joined
Jul 29, 2006
Messages
5,279
I have 3 identical Maxtor 300 GB disks. Currently, I have all 3 of them in a RAID 5 using my motherboard's chipset RAID. Now, I havn't noticed any blistering performance increases (not that I really expected them, but from what I'd heard... :rolleyes:), and I'm now wondering: would it be better to just put 2 of the drives in RAID 0 and just leave the 3rd drive seperate?

600 GB (well, 558 GB, the size of my RAID 5 array) is enough for me, so I'm looking more for performance (i.e. if I put the 3rd hard drive seperate, it's not just for the extra space). Which is better then?
 
What's your usage pattern?

RAID-5 does speed up one access pattern, somewhat - small seeks after random reads. However, that probably doesn't work with onboard SATA raid, you need fairly sophisticated RAID for this speedup to show.

RAID-0 speeds up most other access patterns and will generally be faster for a mix.

Obviously you make a big safety tradeoff there..
 
I don't care much about this "safety" thing, if my hard drive is going to crash, it's going to crash, and I doubt RAID will really help me there.

So basically for just about everything, RAID 0 will be faster?
 
djBon2112 said:
I don't care much about this "safety" thing, if my hard drive is going to crash, it's going to crash, and I doubt RAID will really help me there.

So basically for just about everything, RAID 0 will be faster?
Click to expand...
You are correct, RAID will not prevent a drive failure, but as you have already said, you don't care if your data goes or not. So I shall stop here.
 
djBon2112 said:
RAID 0 will be faster
Click to expand...
in many applications when compared to a single disk. Intelligently laid out multi disk systems may beat R-0 in some usage scenarios, lose in others. All-in-all performance improvements are likely dependent on usage patterns.

Many people support the theory that R-0 is a one-size-fits-all method for performance improvement. Certainly, it is a very simple way to increase STR and combine multiple HDDs, sacrificing uptime. Of course spanning may be less error prone, depending on how it is implemented.

On R-5: I have heard many people argue against putting an OS on a R-5 partition, more specifically the swap file, due to R-5's generally worse random write performance when compared to single-disks or R-1.
 
Well, my usage pattern will be gaming. I want reduced load times in gaming. That's about it really. Any suggestions?
 
That costs money, and I already have these hard drives, I want to use them.
 
You put your three harddrives into raid-5, although you don't care about safety?

And yes, paging space ("swapfile") should be on all drives, but the plain drives, unless you need true hotswap capabilities.
 
uOpt said:
You put your three harddrives into raid-5, although you don't care about safety?

And yes, paging space ("swapfile") should be on all drives, but the plain drives, unless you need true hotswap capabilities.
Click to expand...

I did it because I expcted the same speed as RAID0 plus the security.

What I got was load times and copy rates slower than my old PATA hard drive...
 
djBon2112 said:
I did it because I expcted the same speed as RAID0 plus the security.

What I got was load times and copy rates slower than my old PATA hard drive...
Click to expand...

Of course raid-5 is faster reading (loading programs etc) than plain disk, in particular small random reads.

Unfortunately that only applies to decent raid-5 software. So far I haven't seen really decent software used for onboard SATA raid.
 
djBon2112 said:
I'm now wondering: would it be better to just put 2 of the drives in RAID 0 and just leave the 3rd drive seperate?
Click to expand...

Yes, it's worth a shot.

Here's a suggested configuration:

OS on single drive, in a small partition.
Optional second small partition just for the swap.
Large partition for rarely-used data, and as a backup of "important" parts of the RAID 0 data.

Main programs, data, etc., on RAID 0 array. I suggest 32k stripe size.

Of course you could try measuring performance with different stripe sizes, and even other configurations -- e.g. programs and data on single drive. You might also want to meaure the performance of the existing system before changing it.
 
i run raid0 with two sata1 drives

i'm always the first one done loading BF2 maps.... by a VERY long shot - AND i'm only running a p4 (socket 478) 3.4

although i know 2 gigs RAM helps out

The drives are nothing special... hitachi deskstars that are about 2 years old

in other words - raid0 is the shizznit... I've been thinking about raid5 next time i make a build, but i'll probably just end up with raid0+1 (in other words, a raid0 array backed up by one hard drive.)
 
^^ Yes, don't go with RAID5, it won't help your load times.

I tried a couple benchmarks with the RAID5 array, then redid it with RAID0, and the RAID0 is MUCH faster at both reading and writing.
 
You must log in or register to reply here.
Back
Top