# What's an Optimal RAID 6 Stripe Size?



## Mattyd893

Personally I'd go higher than 64KB if you will be writing large files.

Basically what you said is correct...

For Virtual disks (for virtual amchines) you will have a huge amount of I/Os and a smaller stripe size is needed.
For normal file server type access you have a lot of I/Os and a small to medium stripe size is needed
For a storage device, designed to store large files a larger stripe size will give you the best performance for writing large files.

I would look at 512. What you should do is setup your array, and copy 'x' Gigs of data to and from the array, change the stripe size and do the same again. It's a bit of messing around but it will give you the best idea of where the performance lies.

To work out your exact storage there is a really good, detailed calculator here http://www.wesworld.net/raidcalculator.html you need to find all the details of your drive first though.

On a single array on a single LUN then a 4K sector size will be ideal. You only really need to worry sector size causing allignement issues with multiple arrays. The only other concern is that if you are writing multiple small files all the time then a 4K cluster size might create more slack space, For example, writing a 5K file will wast 3K of a second sector, for your scenario this shouldn't be an issue.


----------



## parityboy

*@OP*

Mattyd893 is correct. In your case I'd look at stripe sizes anywhere from 256KB to 512KB. On my own array I store mostly movies and ISOs, so I use a 256KB stripe.


----------



## cslayer211

Okay, I went with 512KB stripe size because I think it should make it faster to access backup archives.

Now I just hope that Windows Server 2012 stores the backup in a huge archive and not small individual files


----------

