Re: Storage location of temporary files

"Scott Marlowe" <scott(dot)marlowe(at)gmail(dot)com> writes:

> 2008/11/5 Christian Schröder <cs(at)deriva(dot)de>:
>> Tomasz Ostrowski wrote:
>>>
>>> This is wrong. RAID5 is slower than RAID1.
>>> You should go for RAID1+0 for fast and reliable storage. Or RAID0 for
>>> even faster but unreliable.
>>>
>>
>> I did not find a clear statement about this. I agree that RAID10 would be
>> better than RAID5, but in some situations RAID5 at least seems to be faster
>> than RAID1.
>
> For certain read heavy loads RAID-5 will beat RAID-1 handily. After
> all, from a read only perspective, a healthy RAID-5 with n disks is
> equal to a healthy RAID-0 with n-1 disks.

Uhm, and for a read-heavy load a RAID-1 or RAID 1+0 array with n disks is
equal to a healthy RAID-0 with n disks.

RAID-5 should never beat any combination of RAID-0 and RAID-1 with the same
number of drives at read performance. It's advantage is that you get more
capacity.

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Gregory Stark
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