Package org.hyperledger.fabric.metrics

Supports collection of metrics

The main metrics that are available are the statistics around the number of tasks that are running, and how the thread pool is handling these. Note a 'task' is a message from the Peer to the Chaincode - this message is either a new transaction, or a response from a stub API, eg getState(). Query apis may return more than one response. To enable metrics ensure that there is a standard format Java properites file called `config.props` in the root of your contract code. For example this path

myjava-contract-project/java/src/main/resources/config.props

This should contain the following

 CHAINCODE_METRICS_ENABLED=true
 TP_CORE_POOL_SIZE=5
 TP_MAX_POOL_SIZE=5
 TP_QUEUE_SIZE=5000
 

The metrics enabled flag will turn on default metrics logging. (it's off by default) The TP values establish the core thread pool size, max thread poolsize, and the number of of tasks that will wait. (5, 5, 5000 are the default values, so don't need to be explicitly specified). If no file is supplied mertics are not enabled, the values shown for the thread pool are used.

Interface Summary

Interface	Description
MetricsProvider	Interface to be implemented to send metrics on the chaincode to the 'backend-of-choice'.
TaskMetricsCollector	Collect metrics relating to the task execution.

Class Summary

Class	Description
Metrics	Metrics setups up the provider in use from the configuration supplied If not enabled, nothing happens, but if enabled but no specific logger default is used that uses the org.hyperledger.Performance logger