This article provides information on using the sizing guidelines for vRealize Operations Manager 7.5, to determine the configurations used during installation, or post install.

VMware vRealize Operations Manager 7.5.x

By default, VMware offers Extra Small, Small, Medium, Large, and Extra Large configurations during installation. You can size the environment according to the existing infrastructure to be monitored. After the vRealize Operations Manager instance outgrows the existing size, you must expand the cluster to add nodes of the same size.
 

	vRealize Operations Node					Remote Collector (RC)
	Extra Small	Small	Medium	Large	Extra Large	Standard	Large
Configuration
vCPU	2	4	8	16	24	2	4
Default Memory (GB)	8	16	32	48	128	4	16
Maximum Memory Configuration (GB)	8	32	64	96	128	8	32
vCPU: Physical core ratio for data nodes (*)	1 vCPU to 1 physical core at scale maximums
Network latency for data nodes (******)	< 5 ms
Network latency for remote collectors (******)	< 200 ms
Network latency for agents (to vRealize Operations node or RC) (******)	< 20 ms
Datastore latency	Consistently lower than 10 ms with possible occasional peaks up to 15 ms
IOPS	See the attached Sizing Guidelines worksheet for details.
Disk Space
Objects and Metrics
Single-Node Maximum Objects	350	5,000	15,000	20,000	45,000	6,000 (****)	32,000 (****)
Single-Node Maximum Collected Metrics (**)	70,000	800,000	2,500,000	4,000,000	10,000,000	1,200,000	6,500,000
Maximum number of nodes in a cluster	1	2	8	16	6	60	60
Multi-Node Maximum Objects Per Node (***)	N/A	3,000	8,500	16,500	40,000	N/A	N/A
Multi-Node Maximum Collected Metrics Per Node (***)	N/A	700,000	2,000,000	3,000,000	7,500,000
Maximum Objects for the configuration with the maximum supported number of nodes (***)	350	6,000	68,000	200,000	240,000
Maximum Metrics for the configuration with the maximum supported number of nodes(***)	70,000	1,400,000	16,000,000	37,500,000	45,000,000
End Point Operations agent
Maximum number of agents per node	100	300	1,200	2,500	2,500	250	2,000
vRealize Application Remote Collector (*****) telegraf agent
Maximum number of agents per node	100	500	1,500	3,000	4,000	250	2,500
Network latency for Application Remote Collector (to vRealize Operations node or RC)	<10ms

• * It is critical to allocate enough CPU for environments running at scale maximums to avoid performance degradation. Refer to the vRealize Operations Manager Cluster Node Best Practices in the vRealize Operations Manager 7.5 Help for more guidelines regarding CPU allocation.
• ** This is the total number of metrics from all adapter instances. To get this number, go to the Administration page, expand History and generate an Audit Report.
• *** In large configurations with more than 8 nodes, the maximum metrics and objects have been reduced to permit some head room. This adjustment is accounted for in the calculations.
• **** Based on the VMware vCenter adapter.
• ***** vRealize Application Remote Collector discovers applications running on Virtual Machines and collects run-time metrics of the operating system and applications.
• ****** The latency limits are provided in Round Trip Time (RTT).

What's new in vRealize Operations Manager 7.5 sizing

• New way to monitor operating systems and applications: Telegraf agents using vRealize Application Remote Collector
• Performance Improvement with the same footprint: Up to 15% vCPU usage reduction

vRealize Application Remote Collector Maximums

	Small	Medium	Large
vCPU	4	8	16
Default Memory (GB)	8	16	24
Maximum Number of supported telegraf agents	500	3,000	6,000

Note: Note: vRealize Application Remote Collector can be configured for many vCenters, although each of those vCenters can only be monitored by one Application Remote Collector.
If you have more than 6K telegraf agents increase vCPU and Memory of the Large configuration to monitor up to 10K telegraf agents. 
Consider having 20% free vCPU while installing 1K telegraf agents simultaneously as the vCPU usage of vROps VM will be increased 10-18%.
The increase of memory usage depends on the number of services and their configurations on the monitored VM. Memory usage will be increased at least 1-1.5 GB when monitoring 1K OS objects.

Important Notes

• The sizing guides are version specific, please use the sizing guide based on the vRealize Operations version you are planning to deploy.
• An object in this table represents a basic entity in vRealize Operations Manager that is characterized by properties and metrics that are collected from adapter data sources. Example of objects include a virtual machine, a host, a datastore for a VMware vCenter adapter, a storage switch port for a storage devices adapter, an Exchange server, a Microsoft SQL Server, a Hyper-V server, or Hyper-V virtual machine for a Hyperic adapter, and an AWS instance for a AWS adapter.

 

Other Maximums

Maximum number of remote collectors	60
Maximum number of vCenter adapter instances	120
Maximum number of vCenter on a single collector	100
Maximum number of concurrent users per node (*)	10	This is when the cluster is running with all nodes filled with objects or metrics at maximum levels on a 4 large node cluster.
Maximum number of certified concurrent users (**)	300
Maximum number of the vRealize Application Remote Collector telegraf agents	10,000
Maximum number of the End Point Operations agents	10,000

* The maximum number of concurrent users is 10 per node with objects or metrics at maximum levels (For example, 16 nodes Large with 200K objects can support 160 concurrent users).
** The maximum number of concurrent users is achieved on a system configured with the objects and metrics at 50% of supported maximums (For example, 4 nodes Large with 32K object).
 

VDI use case

• A large node can collect up to 20,000 vRealize Operations for Horizon objects when a dedicated remote collector is used.
• A large node can collect up to 20,000 vRealize Operations for Published Apps objects when a dedicated remote collector is used.

 

Constraints

• Extra small configuration is designed for test environments and POC, we do not recommend to scale up an extra small node horizontally.
• If you have >1 node, then all nodes must be scaled equally. No mixing of nodes with different sizes.
• Snapshots impact performance. Snapshots on the disk causes slow IO performance and high CPU co-stop values which degrades the performance of vRealize Operations.
• In HA, each object is replicated in some nodes of a cluster, hence the limit for HA based instance is two times less compare to non HA. 
• vRealize Operations HA supports only one node failure. Avoid single-point-of-failure by putting each nodes into different hosts in the vSphere cluster.

 

Scaling Tips

• Scale up vertically (adding more vCPU/Memory), not horizontally (adding more nodes).

• You can increase RAM size instead of increasing both RAM and CPU.

• Scale down CPU configuration.

Collectors

The collection process on a node will support adapter instances where the total number of objects is not more than 3,000, 8,500, 16,500 and 40,000 on small, medium, large and extra large multi-node vRealize Operations Manager clusters respectively.
For example, a 4-node system of medium nodes will support a total of 34,000 objects.
However, if an adapter instance needs to collect 12,000 objects, a collector that runs on a medium node cannot support that as a medium node can only handle 8,500 objects. In this situation, you can add a large remote collector and pin the adapter instance to the remote collector or scale up by using a configuration that supports more objects.

Recommended sizing can be checked by inputting values on vropssizer.vmware.com, or by inputting values on the attached spreadsheet.