HP Capacity Advisor 7.2 User Guide

Insufficient resources on the VM host:
Smart Solver informs you when the destination VM host has insufficient resources to host all of the
consolidated systems. This can happen when the selected systems do not have enough resource
capacity to place all of the workloads or when workloads cannot be placed on any of the selected
systems. The Smart Solver will try to place as many workloads as will fit, giving you a partial
solution. When this occurs, you can click Return to Step 1 to adjust the attributes and constraints
for the VM host, or Cancel and return to the scenario editor. From there, adjust the resources on
your destination VM host or add another VM host to the automated consolidation simulation. For
more information on this behavior, see “When available systems lack sufficient capacity” (page 176).
Results: Automated consolidation to VMs
Expected results
The solutions show the systems converted to VM guests on VM hosts. These VM hosts are either
existing VM hosts, “what-if” generated template VM hosts, or a combination, depending on what
destinations you selected. When a combination of VM hosts are chosen, the placement of VM
guests goes first to existing VM hosts, and then to the template VM hosts.
Further, as part of the input parameters, you can select to load balance the resulting VM hosts.
This load balancing occurs after and only amongst the target VM hosts that are required for the
consolidation solution. In other words, if the consolidation solution results in any VM hosts being
unused (and therefore, not required in the solution), the unused systems will not be involved in the
load balancing. Only the required systems in the solution are involved in the load balancing.
The resulting solution is the configuration requiring the fewest number of systems with the minimal
requirement for headroom, while taking into consideration resource utilization and utilization limits.
Resources
The placement of VM guests takes into consideration CPU, memory, network I/O, and disk I/O
capacity, and utilization limits. If load balancing (balancing resource utilization across the resulting
systems) was selected, the VM guests were load balanced across the systems that had one or more
VM guests.
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 ranking 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
Fewer systems shown
The Smart Solver solution can contain fewer VM host targets than were originally selected. This
occurs when the workloads fit on fewer systems than originally selected. For example, if systems
A, B, and C are selected as target VM hosts, but all the workloads can fit into VM hosts A and B,
then only VM hosts A and B are shown in the solution.
92 Procedures