We have an i5 system (520) with disks unit type 4328 that have 140 GB capacity. We wanted to extend our storage capacity, so we purchased a drawer with disk type 4327 that has 70 GB. How will the new extension affect our system performance?
If the system has a good controller with lots of cache, it probably won't hurt the performance at all. Two different sized disk units are not usually a problem, but three sometimes are.
Since the system performance depends on the workload, it is probably not possible to predict this with great reliability in advance, and since the capacity already needs to be extended, it is likely that the workload is changing as well.
This was first published in April 2009