SATA Raid vs IDE Raid

D

Dracul

Gawd
Joined
Jan 8, 2002
Messages
774
I'm going to buy another motherboard with raid since i'm adding a 3rd 120gb drive to my server (specs in sig).

Now my question is am i better off finding a motherboard with IDE raid, or should i use SATA raid with IDE adapters? Will i notice a difference in performance between the two?
Also from what i was reading, the array is only going to be as big as the smallest drive. and right now i have 1 160gb and 2 120gb drives. so does this mean that 40gb of my 160gb drive is going to be unused?
 
1. Don't use Serial ATA adapters if you don't have to. Slapping an adapter on won't improve performance one bit. It might even degrade performance slightly.
2. RAID should only be done with similar or identical drives. In fact, you're really asking for trouble unless you use drives of the same make and model. Definitely leave the 160 GB drive out of the array.

Do you know what you're getting into? RAID of any kind, when improperly executed, puts your data at increased risk of total loss. Are you willing to risk that? Do yourself a big favor and read Storage Review's RAID guide:

http://storagereview.com/guide2000/ref/hdd/perf/raid/index.html
 
well i do kinda know what i'm getting into.. and i've set up raid on a dell poweredge server at my old high school a couple years ago and while it was kinda different (4 10gb hotswap drives) i think i'll be ok.

As for the hard drives i'll probably get rid of the 160gb and replace it with another identical 120gb.
however just for my information what would happen if i used the 160gb in the array?

I'll just use ide raid and not bother with sata, i just wasn't sure if the sata controllers were better than the ide ones.
 
If you used the 160 GB drive, only 120 of it would be included in the array. It's questionable whether one could reclaim the remaining 40 GB for a usable partition.
 
ahh ok... i was kinda thinking that was going to happen once i started reading stuff about the different levels, but i wasn't sure if there would be other problems associated with using it as well..
 
There could easily be more problems as well. I've never tried it, and since there's hardly an advantage to trying it, just don't...
 
different drives employ different algorithms
in fact that is one of the primary reasons some drives perform better than others, and some perform better in RAID arrays at various levels
it comes down to how the drive uses its own cache, so mixing those different strategies means the RAID controller needs to deal with drives that arent acting the same way, generally this just degrades performance, but not always


http://www.pcguide.com/ref/hdd/op/cache.htm
http://www.pcguide.com/ref/mbsys/cache/layers.htm
http://www.pcguide.com/ref/mbsys/cache/funcComparison-c.html
(and then some RAID controllers have their own cache)


http://www.iozone.org/

There are in fact many layers of cache in a modern PC. This does not even include looking at caches included on some peripherals, such as hard disks. Each layer is closer to the processor and faster than the layer below it. Each layer also caches the layers below it, due to its increased speed relative to the lower levels:
Click to expand...
 
You must log in or register to reply here.
Back
Top