</I>1. Application Description
1) Service Description
A performance counter defines the measurement items of a measurement object and can be used for network performance assessment, network optimization, and fault detection.
The following concepts help you better understand a performance counter:

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• Counter: (also counter timer), data that must be collected for a measurement, such as number of requests and service traffic   
• Function subset: (also called measurement unit), a set of measurement counters with the same attribute, for example: the function subset of Ethernet port measurement refers to statistics of different types of traffic over an Ethernet port.  
• Function set: a set of multiple function subsets with the same attributes, for example, the function set Measurements Related to Network Layer consists of three function subsets: IP Measurement <Network.IP>, IPv6 Measurement <Network.IPv6> and Tunnel Measurement <Network.Tunnel>.  
• Object type: (also called measurement object) a physical entity or logical entity.  
• The following figure shows the relationship between the object type, function set, function subset, and counter.
  

                 
  
2) Documentation Description
For details about how to measure performance counters for Pico, see the performance counter reference.
The performance counter references of all versions are described by object. The following figure shows the document structure.
  
  
2. Highlights
The counter relationship is provided.
The counter relationship is added to the description of the function subset. Therefore, you can conveniently query and understand counter relationships covering counters of a maximum of nine levels.
   
  3. Reference Documents

Product	Version	Link
BTS3911B	V100R012C10	Pico BTS3900 Performance Counter Reference
BTS3911B	V100R013C10	Pico BTS3900 Performance Counter Reference
BTS3911B	V100R015C10	Pico BTS3900 Performance Counter Reference

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