IT question about disc arrays and RAID

[DOC]

3.5" diskettes all the way.

[esaabye]

For DBA's it is all about IOPS which is a function of the disk speed and the number of them in an aggregate. In the old days we would spend lots of time breaking the BD into table groups and speading across different disk types based on performance needs.

Now we buy an san with data progression and let the controllers move blocks around so that the more popular data is on the outside enge of the fastest spindles. Now we are starting to get SSD and large flash arrays with tons of caching at 'reasonable' pricing thus further removing the planning needs.

Take a look at some of the larger san provider sites (EMC, Dell, HP) and some of the niche like Nimble and read the cool-aid. They will all spin it differently but in the end it is a function of speed of disk times number of disk.