The end of Raid as we know it .. RAID is dead, long live RAIS !
I somehow totally missed this thread , started and summarized by Jeremy Cole on the death of Raid ..
In Yes Jeremy, RAID Really Is Dying , Kevin Burton makes a good point ..
Most large scale out shops should probably be using a redundant array of inexpensive servers.
or RAIS , the difference between a Redundant Array of Inexpensive Servers an Inexpensive Disks being that you don't need expensive Controllers for the Inexpensive Servers .. This is exactly what I have been telling people for a while now..
In the summary posting Jeremey also points out
data partitioning is the only game in town, cache everything, and use MySQL replication for high availability and redundancy.
And when you do replication to multiple servers, why still add RAID to your design, your data is already replicated on multiple disks. Putting it on even more disk is just a pure waste of money.