Planning Virtualization?

A common question that most IT managers are faced with while they mull on virtualization is what kind of a system should I use? Do I need a 2 socket system? a 4 socket system?

Reality in my view, it is more like designer wear and there is no ‘one size fits all' generic answer for such question. There are few things (not exhaustive by any means) IT managers that are planning virtualization need to understand to come to that conclusion are

  • How many servers are being consolidated?

  • Workload and compute horsepower: What are the workloads being consolidated? What is the average utilization of the workload? What is the maximum utilization expected from the workload (so that you anticipate for the max and the datacenter capability does not fall apart if the workload utilization increase)? An overall look at the compute horsepower requirement to run the VM with the workload.

  • Memory: How much memory is required per VM to run at the acceptable or required quality of service guarantees of performance?

  • Manageability comfort and VM variation/headroom: The number of VMs the IT manager is comfortable putting on a same system either for ease of manageability, downtime managements, resource scaling if VMs get over utilized or over subscribed at peak demand, and/or also any intuitive comfort level of mixing different workloads or OS environments.

In my opinion, for high level of server consolidation with memory and I/O intensive workloads or VMs, less predictive workloads, and workloads that demand more headroom for peak demands, a 4 (or higher) socket system could be more beneficial. For consolidation to raise server utilization with very predictable and stable workload that may be smaller applications, a 2 socket system could be beneficial.

Feel free to write your opinion, or experience.

Some resources: