Topology Metrics

The metrics measure the virtual topology cached by a given MidoNet Agent. The virtual topology consists of virtual devices, such as bridges, routers, ports, chains, rules, etc. When a device is requested in order to process a packet that must traverse or otherwise requires that device, the MidoNet Agent loads the device from the Network State Database, and caches it for later usage. In addition, the agent keeps a notification stream open to the NSDB for that devices, such that future changes of the device are notified to the agent, updating its internal cache and invalidating any flows that have previously been established using that device’s older configuration.

Some virtual topology metrics are global, whereas others are reported for each device class, which can be one of the following: Bridge, Chain, Host, IPAddrGroup, LoadBalancer, Mirror, Pool, PoolHealthMonitorMap, Port, PortGroup, Router, RuleLogger and TunnelZone.

Global Metrics

NameDescription

VirtualTopologyGauge.devices

A gauge for the number of devices stored in the virtual topology cache.

VirtualTopologyGauge.observables

A gauge for the number of open observable streams that report changes for the devices stored in the virtual topology cache.

VirtualTopologyGauge.cacheHit

A gauge for the cache hits when a device was requested by the packet pipeline when simulating a packet. A cache hit means that the device was available immediately, and the packet simulation was not interrupted.

VirtualTopologyGauge.cacheMiss

A gauge for the cache misses when a device was requested by the packet pipeline when simulating a packet. A cache miss means that the device needed to be loaded from the NSDB, requiring the packet simulation to be postponed until the device became available. Cache misses lead to higher packet processing latencies.

VirtualTopologyCounter.deviceUpdate

The number of updates the virtual topology caches receives for all cached devices.

VirtualTopologyCounter.deviceError

The number of errors the virtual topology caches receives for all cached devices.

VirtualTopologyCounter.deviceComplete

A counter for the cached devices that were deleted.

VirtualTopologyMeter.deviceUpdate

A meter for the device updates received by the virtual topology for the cached devices.

VirtualTopologyMeter.deviceError

A meter for the device errors received by the virtual topology for the cached devices.

VirtualTopologyMeter.deviceComplete

A meter for the devices deleted from the virtual topology.

VirtualTopologyHistogram.deviceLatency

A histogram with the latency of loading a device from the NSDB.

VirtualTopologyHistogram.deviceLifetime

A histogram with the lifetime of a device in the virtual topology cache.

Questions? Discuss on Mailing Lists or Chat.
Found an error? Report a bug.


loading table of contents...