Application Awareness Part 1 CPU

In my previous post concerning Application Awareness, I talked about resource utilization and the need for a workload manager type management layer which provides the ability to manage applications from the resource perspective. I would like to break that down to the different resources (core four of CPU, Memory, I/O and Network) for discussion.

From the CPU perspective, the good news is the number of cores is increasing. We started out with a single core, then added hyper threading, to dual cores, four cores and now six cores per processor. This trend aids in the move to virualization and 64 bit OS/Applications as the 32 bit OS's cannot utilize more than 4 cores and most only two cores. What this means is for the virtual world, there are a number of cores available for an ever increasing number of virtual machines per host. That's the good news. The bad news is there are only so many cores to share.

A brief note on how I equate cores for business people. A core is a resource where only one instruction can occur at a time. So sorting a report or fetching a record from disk is an instruction.

There's more good news in that the core speed is increasing as well which means the applications can run faster but more importantly, the core can process the instruction and be free for another instruction/vm to use that resource. So, let's break this down a bit further in how application awareness comes into play here. As applications grow and scale, they are utilizing the increased size (speed) and number (cores) more and more. What this means to the application awareness discussion is the need to separate out which applications need more CPU (CPU intensive processing) and Cores (multi-threaded applications to process in parallel).

In the physical world, this is not a problem. An application is assigned to a physical node and the application gets all of the resources. In the virtual world, this is a four step process.

1. The creation of the VM requires the number of processors (cores) to be defined.
2. The VM needs to be placed on a host which has enough processors (cores) to start the VM.
3. The application needs to perform within limits for Service Level Agreements (SLA's) to be defined and meet.

While VMware's Distributed Resource Scheduler (DRS) provides the ability to set priorities (once the VM is running) at the VM layer to balance resources and ensure VM's have the resources they need, this is a manual process at best. In the cloud where the operations staff is far removed from the business/application owner, taking the step towards application awareness will become vital for the performance and availability of applications in the cloud.

The cloud providers will need to factor into their portals the creation, placement and performance of the VM's to maintain customer satisfaction. Moving towards Application Awareness is the first step.