Network Topology metrics reference

This document describes Cloud Monitoring metrics and metadata, which you can view in a Network Topology visualization for each entity and connection.

  • Metadata describes data such as name, description, and location.
  • Metrics describe data such as traffic, latency, and packet loss, which are the supported metrics for connections.

For each Network Topology hierarchy, the Google Cloud Console displays a single metric for Compute Engine virtual machine (VM) instance entities and region entities, as well as for connections. You can change this default metric.

For more information, see the Network Topology overview and the Graph interface overview.

For steps describing how to work with metrics and metadata, see Using Network Topology.

Metrics for VM or regional entities

This section lists metrics for VMs or regional entities.

Entity Metrics
VM
  • CPU utilization
  • Memory usage percentage
  • Disk usage percentage
Region
  • Traffic

Metrics for connections between entities

This section lists metrics for connections between entities.

Some connections support packet loss or latency metrics. Packet loss is based on probers that estimate the packet loss that you might experience, while latency and other metrics are based on your own traffic.

If there are not enough probes or traffic to calculate a high confidence value for packet loss or latency, Network Topology displays an asterisk (*) next to the value on the graph. For more information about how these metrics are calculated, see the Metrics section of the Performance Dashboard overview.

Connections in the VM hierarchy

This section lists metrics for connections in the aggregation hierarchy where VM is the base entity. For more information about entities and their aggregation hierarchies, see Resources and traffic.

Connection Metrics
VM to VM1
  • Traffic
  • Latency: based on round-trip time (RTT)
  • Packet loss2

1 VM-to-VM flows are not available at all aggregation levels. For example, the VM-to-VM flow is not available, but the VM-to-region flow is available.

2 Packet loss is available only for regions and zones.

Client to load balancing

This section lists metrics and metadata for traffic from external or internal clients to different types of Cloud Load Balancing.

Entity (node or edge) Metrics
External client3 to HTTP(S) Load Balancing
  • Traffic: based on request bytes count and response bytes count
  • Latency: based on Frontend RTT
  • Request count
  • HTTP error response count: based on responses by response code class
  • HTTP error response percent: based on response fraction by code class
  • Client-side error rate (total): based on CSM metrics
External client to SSL Proxy Load Balancing or TCP Proxy Load Balancing
  • Traffic: based on inbound traffic and outbound traffic
  • Latency: based on Frontend RTT
  • Current open connections: based on open connections
  • Connections open rate: based on new connections per second
  • Connections close rate: based on closed Connections per second
External client to Network Load Balancing
  • Traffic: based on external bytes count for egress and ingress

3For external clients, Network Topology supports only aggregation levels from Country and higher.

Load balancing to backend instance groups

This section lists metrics and metadata from different types of Cloud Load Balancing to instance group backends.

Entity or connection Metrics
HTTP(S) Load Balancing to backend (instance group)
  • Traffic: based on backend request bytes count and backend response bytes count
  • Latency: based on backend latencies
  • Request Count: based on backend request count
SSL Proxy Load Balancing or TCP Proxy Load Balancing to backend (instance group)
  • Traffic: based on inbound traffic and outbound traffic
Internal TCP/UDP Load Balancing to backend (instance group)
  • Traffic: based on inbound traffic and outbound traffic
Network Load Balancing to backend (instance group)
  • Traffic: based on external bytes count for egress and ingress