VMwareAria.github.io

Capacity Engine

Definitions

• Total Capacity: All available resources (CPU, memory, disk space, IOPS) in the environment.
• Usage: Resources presently utilized by VMs and system services.
• Demand: Resources needed by VMs; equals usage unless a resource is constrained.
• Usable Capacity: Total capacity minus a buffer set aside for workload spikes.
• Usable Capacity after HA and Buffer: Usable capacity less resources reserved for HA failover.

The capacity engine analyzes historical utilization and projects future workload using real-time predictive capacity analytics.

INPUT:

• Demand
• Usable Capacity metrics

GENERATED OUTPUT:

• Time Remaining (estimated time before full utilization)
• Capacity Remaining (available capacity)
• Recommended Size (optimal resource configuration)
• Recommended Total Capacity (required future capacity)

Recommended size

Determined by projecting utilization for a specific period. The recommended size does not include HA settings. To maintain conservative recommendations, VMware Aria Operations imposes caps on the recommended size generated by the capacity engine.

*) Oversized: Aria Operations limits oversized recommendations to 50% of the current allocation. For instance, if a virtual machine with 8 vCPUs #historically only used up to 10% CPU, the recommendation is capped at reclaiming 4 vCPUs rather than 7.

*) Undersized: Aria Operations limits undersized recommendations to 100% of the current allocation. For example, if a virtual machine with 4 vCPUs consistently experiences high resource utilization, the recommendation is capped at adding 4 vCPUs instead of suggesting 8.

Capacity calculations for a Conservative Risk Level

• Customize the level of conservatism

• Prioritize stability
• Ensure enough resources for future growth and demand.
• A cautious approach to capacity planning
• Lower consolidation ratios + higher resource overhead

Capacity calculations for a Aggressive Risk Level

• Aim to maximize resource utilization and minimize overhead.
• Assumes a higher tolerance for risk
• Allows for more aggressive allocation of resources.
• Result: Higher consolidation ratios + tighter resource utilization.

#####

• Momentary Peaks: Short-lived peaks that are a one-time occurrence. Not significant enough to require additional capacity.
• Sustained Peaks: Last for a longer time and impact projections.
• Periodic Peaks: Cyclical patterns or waves. (hourly, daily, weekly, monthly, last day of the month, etc)

What is Rightsizing? It should be pretty obvious?

• It’s a proactive practice, not a one-time work!
• Maximizes performance efficiency
• Reduces costs
• Ensures seamless alignment with requirements