Manage Metrics

Overview

Managing metrics is a key aspect to the performance of the Joule runtime. By applying the compaction policy this will reduce the memory footprint required of the JVM and therefore the number of GC cycles.

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Runtime Policy

This section configures when to start and how frequently metrics are calculated. Below the metrics computation will start after 2 minutes on process startup and thereafter every 1 minute.

Example

truncate on start: true
compaction policy:
  frequency: 8
  time unit: HOURS

Compaction Policy Attributes

Attribute	Description	Data Type	Required
frequency	Frequency metrics are computed. Minimum 15 second computation cycles	Long Default: 1
startup delay	First compute cycle delay.	Long Default: 5
time unit	Time unit used to set the scheduled processing policy Supported units: SECONDS, MINUTES, HOURS	TimeUnit Default: MINUTES

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Metric Management Attributes

Each metric definition includes management attributes to control how the metric table is managed throughout the Joule process lifetime. Since Joule uses an in-memory database the size of table needs to be managed

Attribute	Description	Data Type	Required
truncate on start	Truncate the mtric tables on startup	Boolean Default: true
compaction policy
frequency	Frequency table compactions will occur	long Default: 1
time unit	Time unit used to set the scheduled companion policy Supported units: MINUTES and HOURS	TimeUnit Default: HOURS