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Contents


Purpose

This “document” shows some informative examples in various formats and is not a specification itself. We encourage opening each example with a natural language explanation and summary of the semantic content, followed by RDF in at least the two most popular serializations (RDF/XML and Turtle).

Running Example: Performance Monitoring Data about a Computer System

This is a running example, i.e. the working group is using it as a concrete example to flush out issues that will influence the resource definitions. “Running” means that it evolves over time; as we get at least provisional consensus on a solution to the issue-of-the-day, we add that and move on.

Semantic content of the record:

  • CPU Utilization: 80 percent
  • Average number of database connections in use: 68
  • Time the data was collected: see value in record
  • A link to the Computer System resource whose data the record contains
    • In this example, the link is circular, i.e. the Perf Mon resource is also the Computer System resource.
    • The two just as easily could be separate resources.
    • The WG intent is to use normal RDF linking so the choice is left to provider implementations, and clients need not behave any differently.
  • A set of “top n” process information
    • The value of “n” is intentionally left open. For the purposes of meeting discussions/strawmen we assume n<=5.
    • CPU, real memory, and virtual memory each have a top-n list
      • CPU: 1=sdfdl, 2=vsmon
      • real: 1=vsmon, 2=firefox, 3=iexplore
      • virtual: 1=firefox, 2=vsmon, 3=iexplore
    • Each of the process names occurring in the preceding lists have their own observed metrics: cpu util, real, virtual memory usage

List of exemplary representations (newest first; older ones might contain only a subset of the semantic content above). The comments in Turtle representations typically include useful information, the most important of which is duplicated after this list.

  • 2012-07-18: Strawman: hash URIs replace blank nodes, various list representations tried out
  • 2012-07-12: Strawman: adds “top 5” process consumers of cpu, real, virtual
  • 2012-06-28: Adds linking a record to the resource it describes, where the link target is a separate resource
  • 2012-06-20: Comparing re-use options: oslc:Property and oslc_ems:Measure

Other useful information about the example, based on WG decisions made to date:

  • We are attempting to [[PmArchitecturalDirectionV2#Re_use_of_Other_Vocabularies][re-use existing vocabularies].
  • pm:New… means a new definition is needed - it’s a placeholder. PerfMon would define any URIs needed.