Long Term Monitor Metrics (LTM)

Long term monitor metrics, as the name indicates, are the metrics that are collected for a resource for a longer term monitoring perspective. They are useful for continuous ongoing monitoring of the managed system.

Long term monitor metrics API is used to fetch the Long Term Monitoring (LTM) metrics from the Hardware Management Console (HMC). The LTM metrics provide data that is collected from Power Hypervisor (PHYP) and Virtual I/O Server (VIOS). The LTM metrics are collected at every collection interval (30 seconds) and are retained in HMC for 30 minutes. After 30 minutes, the collected metrics are purged from the system.

Resource

/rest/api/pcm/ManagedSystem/{uuid}/RawMetrics/LongTermMonitor
/rest/api/pcm/ManagedSystem/{uuid}/RawMetrics/LongTermMonitor?StartTS={StartTS}&EndTS={EndTS}
Since: Version 1_1_0

Quick properties

The API accepts start timestamp and end timestamp as its quick properties. If they are specified, the API responds within the specified duration.

Table 1. Quick properties
Quick property Description Format
StartTS Start timestamp is an optional parameter. If specified, the API returns available LTM metrics after the specified time. yyyy-MM-ddTHH:mm:ssZ
EndTS End timestamp is an optional parameter. If specified, the API returns available LTM metrics on or before the specified time. yyyy-MM-ddTHH:mm:ssZ
Table 2. Supported methods
Method Description Internet media type
GET This API retrieves the long term monitoring metrics for a managed system. The response is returned as an Atom feed to the consumer. The Atom feed contains the Atom links to the LTM JSON files. There is one JSON file for PHYP and one JSON file for each VIOS on the managed system. The Atom link is a web link to the actual JSON file. The content can be retrieved by using the Atom link. application/xml

Response

Successful execution of the request is returned with response code 200. In response the application returns Atom feed and Atom entries. The attributes of the Atom feed are as follows:

  • Id: UUID of the managed system
  • Updated: Timestamp of the last available LTM metrics data collection in the response
  • Title: Name of metrics category
  • Subtitle: UUID of the managed system
  • Link: Type application or JSON link to the LTM JSON data
  • Generator: Name of console

The Atom feed has series of Atom entries. The attributes of the Atom entry are as follows:

  • Id: UUID of the managed system
  • Updated: Start timestamp of the LTM JSON
  • Title: Name of metrics category and system type
  • Published: End timestamp of the LTM JSON
  • Link: Type application JSON, link to the LTM JSON data
  • Author: Name of console
  • Category: Indicates the source of the metrics. There are two main sources for the metrics:
    1. PHYP: For any managed systems, there is only one Hypervisor. The utilization metrics are gathered from the PHYP.
    2. VIOS: For any managed systems, there can be 0 or more VIOS. The utilization metrics are gathered from VIOS. The ID field has a value of VIOS id. For example, if the id = 1, then the category is vios_1. The metrics are generated by VIOS with VIOS id 1.

The application collects data at every collection interval and generates one snapshot of the system utilization. Each snapshot corresponds to one or more Atom entries.

The metric data is supplied in the JSON format. The following links provide JSON specification from PHYP and VIOS: