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RAID 0 Stripe and cluster size help

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Hey, im pretty new to raid and was wondering what stripe and cluster size to use.

I want to pair up two 120 gig seagate SATA drives in raid 0.

I kind or understand what stripes and clusters are.

The size of the Stripe is the ammount of data each drive will hold before before moving onto the next drive to span the data across a number of drives.. or something

And cluster size would be the same as what cluster size means with normal ntfs or fat32 partitions.

What i dont understand is the preformance gain of changing these and i dont know what sizes would be best.

My specs are:

Shuttle SN85G4 v2

XP64 2800+

1 gig of ram

blah blah

It has a silicon image SIL3512 chipset.

Also does changind the cluster and stripe sizes use more cpu and stuff? OR because its hardware (no idea how good this silicon image stuff is, onyl sued highpoint) should it calculate everythinjg it self without using the cpu?

Thanks for your time :)

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I was planning on using the defult setting is that exists, but i do understand that too little a stripe will mean that latencies bog you down, and too large a stripe will mean that drive seek times will bog you down.

So i was wondering what the most common settings would be. But from what you have said i supose the preformance gain/loss is minimal?

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I think what he's saying is that RAID0 is a waste of time, no matter what cluster and stripe settings you try. Use your 1st disk as a system drive and the other disk as you swapfile/scratch disk and you'll be much further ahead.

Spinme

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So what your saying is raid0 is not really that much faster than two individual disks?

I did have a WD800jb which was relativly fast but id like to have shorter loading times in games and a faster boot up etc so i thought it would be a good idea to go Raid0 with two drives.

sorry but im slightly confused :lol::rolleyes:

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Read the FAQ. It's all in there -- what cluster size should I use, why RAID does not improve performance as much as you think it will, etc.

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Normally, you want the two drives on your RAID-0 array servicing different I/O requests, so your I//O throughput can go up. (This is only relevant if you have a multithreaded I/O load

which *has* many I/O requests pending at once, of course). However, for really big transfers, you want both heads to help your read bandwidth.

The basic tradeoff point is where it's better to let one drive finish reading than to wait for the other to seek to help. I.e. transfer rate/(seek time + rotational latency). With most current

hard drives this works out to be about 256K.

It can be argued that, since an average read starts halfway through a stripe and you want this much data before asking the second head for help, you want a stripe size twice that.

Anyway, the fine tweaking is application-specific. The main point is that too small a stripe size will generally cost you more than too large.

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I think what he's saying is that RAID0 is a waste of time, no matter what cluster and stripe settings you try. Use your 1st disk as a system drive and the other disk as you swapfile/scratch disk and you'll be much further ahead.

Spinme

What will happen if one of the drives in your suggested setup fail ?

Can he just pull the drive out and replace it with a new one and then everything is the same way it was before ?

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I think what he's saying is that RAID0 is a waste of time, no matter what cluster and stripe settings you try. Use your 1st disk as a system drive and the other disk as you swapfile/scratch disk and you'll be much further ahead.

Spinme

What will happen if one of the drives in your suggested setup fail ?

Can he just pull the drive out and replace it with a new one and then everything is the same way it was before ?

As compared to guaranteed loss if either drive fails in a raid0......?

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I think what he's saying is that RAID0 is a waste of time, no matter what cluster and stripe settings you try. Use your 1st disk as a system drive and the other disk as you swapfile/scratch disk and you'll be much further ahead.

Spinme

What will happen if one of the drives in your suggested setup fail ?

Can he just pull the drive out and replace it with a new one and then everything is the same way it was before ?

As compared to guaranteed loss if either drive fails in a raid0......?

It's not guaranteed. Anyone concerend with data loss, wouldn't rely on either method. If your PSU goes "POP !" then where you at ? You got a pair of KFC extra crispy HDD's either way.

If you are someone who has to have all the speed you can get, surely, a large third drive would be the quickest solution to back up your array.

The point I made was you are going to have to reinstall your OS regardless of which drive fails. Your set-up or his.

Back it up, then STFU.

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Not true, Buddy. Only if the OS drive fails in the case of one OS drive and one app drive. So a 50% chance... but in both setups you should back up your important data. RAID0 gives a higher overall chance of lost productivity and downtime, though. Mean time to repair is also likewise longer.

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Not true, Buddy.  Only if the OS drive fails in the case of one OS drive and one app drive.  So a 50% chance... but in both setups you should back up your important data.  RAID0 gives a higher overall chance of lost productivity and downtime, though.  Mean time to repair is also likewise longer.

Yeah right. Install all your apps to the second drive, and see how far your OS's registry lets you get into a boot up. Either drive fails............and it's.....

"Farewell and adeiu to you fair Spanish ladies........"

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