Re: 4 drive raid -0 in vista
"PNutts" <pnutterfield@hotmail.com> wrote in message
news:71E010BD-45B8-4A61-8B60-0A33CB6466B4@microsoft.com...
>
>> To me, it's foolhardy. It isn't worth running that extra risk for a
>> non-existent or tiny speed improvement.
>>
>
> I'm curious... Why is it considered extra risk? There is a certain risk
> that
> any given hard drive will fail, but it remains the same for each drive and
> is
> not doubled with two drives. Each drive still carries that same risk. For
> example, if each drive has a 1 in 100 chance of failure, you have two
> drives
> that each have a 1 in 100 chance of failure. If you do combine those
> numbers,
> you get a 2 in 200 chance of failure which is still 1 in 100. I hope my
> examples are clear.
>
> I should admit I am hardly objective as I run RAID0 for my OS and the
> performance increase is substantial.
Ken is right. It is not uncommon for say in 2 drives, 1 _will_ fail in 5
years.
So if you have 2 drives, and the OS is on one, there is a 50% chance in say
5 years it will fail. If it is the OS drive, you are dead. If it is the
alternate or back, it is OK except for the data on it but the OS will/should
boot.
Where as if your OS is spanned on 2 drives then the chance becomes 1, as
either drive is failure, probable failure if one fails in 5 years.
If using RAID, I much prefer 0+1, which really does kick read performance
considerably when used with 3 or more drives. But also reduces risk of
since drive failure being an issue to near zero. If using very large
quantities of disk such as a data center, RAID 0+1 or hybrids like RAID 50
work well. But for RAID 50, you need 10 or more disks to do correctly. For
home users, RAID is generally something you will not do. And if you do,
RAID 1.
No, RAID 0+1 with 3 drives is not a typo, have done this and it does work.
One of the questions I have been know to ask "disk RAID gurus" and most get
wrong.