Chuck Lucas wrote:
> "Daniel Morgan" <damorgan_at_x.washington.edu> wrote in message
> news:1066587431.204277_at_yasure...
>
>>You are correct on all points.
>>
>>But what version you implement can make a big difference. I'd stay away
>>from RAID 5 and vendor RAID
>>implementations with numbers like 2 and 4.
>
>
> What's wrong with RAID 5?
With Raid-5 the redundancy information is stripped across all disks.
For EVERY data block which is written to a RAID-5 volume the parity
block must be recalcuated and also written to disk. For all intents
and purposes RAID-5 doubles the number of write operations to disk.
As the percentage of WRITE to READ operations increases available
useful/application disk throughput decreases.
Received on Mon Oct 20 2003 - 19:39:25 CDT
