HP Matrix Operating Environment Software - Manual (Page 115)

Resource capacity. Workloads that specify utilization limits for a metric (for example, memory
or disk I/O) can only be placed on resources that define a capacity for the corresponding metric.
In other words, if you specified that a workload never exceed 100% memory utilization, that
workload can only be placed on a system for which total memory capacity is known.
Utilization limits. Every workload selected must have at least one utilization limit applied before
using the Smart Solver. This can be any type of utilization limit, including the default global
utilization limit.
Headroom rating The headroom rating shows the amount of available resource above the
existing resource utilization that will exist for the resulting solution in the simulation. Among
the solutions that require the same target systems, the solution with the tightest fit is shown.
Possible anomalies in the results
The load balanced results appear unbalanced. The solution may not look balanced because
smaller systems generally are assigned a smaller percentage of usage than larger systems, and
very small systems may end up with no workloads at all.
For example, a large 16 GB system at 87% memory usage has 2 GB of headroom, and a smaller
4 GB system at 87% has only 500 MB of headroom. Aiming for 87% usage on both systems would
not yield a balanced solution. Instead, a balanced solution is to fill the larger system to 87% and
fill the smaller system to only 50%. With this placement, workloads placed on either system will
have the same amount of headroom to grow (2 GB).
No apparent change from original configuration. The solution may be the same as the original
scenario, and it looks as though no computation was performed. Actually, with the current
attributes and constraints, the Smart Solver could not find a better solution than the current
configuration of systems. This means that the current configuration is the current best solution.
A message displayed in BLUE text indicates that the results are not an error (errors are displayed
in RED text).
No apparent change on one or more systems. The solution may show no change on one or
more destination systems. Thus, it may appear that the Smart Solver did not include the server
in its computations. In actuality, the Smart Solver determined that as part of the best solution, it
was best to leave these target systems with their original configurations.
Fewer systems shown. The Smart Solver solution can contain fewer destination servers than
were originally selected. This occurs when the workloads fit on fewer servers than originally
selected. For example, if servers A, B, and C are selected as destinations, but all the workloads
can fit onto servers A and B, then only servers A and B are shown in the solution.
Smaller systems appear unused. The solution may not display smaller systems, making it
appear as if the smaller systems were not included in the Smart Solver computations. In actuality,
when the Smart Solver attempts to place the workloads on target systems, it accounts for the
robustness of those systems. If the workloads fit on larger, more robust systems and the smaller
systems go unused, the solution will display only the larger, used systems.
For example, if there are two large systems and two small systems, the solution may show only
the two large systems, and load balancing will occur only on those two systems.
Automated solution finding: Workload stacking
HP Insight Capacity Advisor software can automate a workload stacking solution, where you
set which servers (existing or newly created) you want the workloads to be on and set optimization
parameters. HP Insight Capacity Advisor software then calculates and displays the best results
for moving the workloads based upon the parameters that you provided. This allows you to see
the predicted results of moving existing workloads onto selected physical systems.
This section describes the procedures for automating workload stacking.
Automating time-consuming simulations 115