A metric is the name TrueSight Pulse uses for anything that can be graphed. Metrics are collected in various ways but are typically gathered by polling some service on a regular interval (1 second being the smallest). Once polled, the metric is sent back to TrueSight Pulse where it is aggregated and rolled up to several higher order time intervals. Using this technique, TrueSight Pulse can quickly display data at arbitrary "zoom" or time periods so trends can be spotted quickly.
What's in a name?
When creating metrics in TrueSight Pulse there are two rules to metric names:
- A new metric must have a globally unique name
- Once created, metric names cannot be changed
The reason for these restrictions is that a metric is only as good as the mechanism that is providing the data. Thus, the quality and accuracy of metric data may differ. TrueSight Pulse aims to provide a diverse ecosystem of plugins and other third party metric data providers which allow users to pick what is best for their needs. Using the above restrictions means that those that provide metrics (with their plugins or by other means) can establish a reliable reputation for that metric data based on the name.
A metric will fall into one of the three follow categories:
There is a set of metrics defined by the system that get collected by the TrueSight Pulse agent. These include:
- MEMU - Overall memory utilization
- CPU - Overall CPU utilization
- DISKW - Number of disk write operations
- DISKR - Number of disk read operations
- NETRB - Number of bytes received
- NETWB Number of bytes sent
- DISKWB - Number of bytes written to all disks
- DISKRB - Number of bytes read from all disks
2) Private use
If you have some arbitrary source of metric data you can graph this by first creating a metric using the Metrics tab in Settings. After this, just use the API to add your measurements as they occur.
3) Public use
This category of metric is typically used when creating a TrueSight Pulse community plugin. You first create the new metric using the Metrics tab in Settings. After this you will create your plugin, listing the metric(s) you created in your plugin description file. When a user adds your plugin, new instances of the metric(s) will be created within that user's account which will reference the original metric(s) you created.