10 Discovery of Windows performance counter instances

Overview

It is possible to discover object instances of Windows performance counters. This is useful for multi-instance performance counters.

Item key

To configure the discovery rule, use the following item:

• perf_instance.discovery[object]

Note that the object name may be localized. For example:

perf_instance.discovery[Processor] # The object name is in English.
       perf_instance.discovery[Processador] # The object name is in Portuguese.

Alternatively, to ensure that the object name is provided in English, independent of OS localization, use the following item:

• perf_instance_en.discovery[object]

For example:

perf_instance_en.discovery[Processor]
       perf_instance_en.discovery[Memory]

Supported macros

The discovery process will return all instances of the specified object in the {#INSTANCE} macro:

[
           {"{#INSTANCE}":"0"},
           {"{#INSTANCE}":"1"},
           {"{#INSTANCE}":"_Total"}
       ]

This macro may be used in the prototypes of perf_counter[] and perf_counter_en[] items.

For example, if the item key used in the discovery rule is perf_instance.discovery[Processor], you may create the following item prototype:

perf_counter["\Processor({#INSTANCE})\% Processor Time"]

Note:

• If the specified object is not found or does not support variable instances, the discovery item will become NOTSUPPORTED.
• If the specified object supports variable instances but currently does not have any instances, an empty JSON array will be returned.
• Duplicate instances will be skipped.