Region Metrics
Metrics are collected by Akka actors and stored in an H2 Database. There are different tasks going on, at different time intervals:
- on startup, set the loglevel to INFO for all RegionServers (only if init.set_hbase_loglevels_to_info is true), this is required for "CompactionMetrics" to work, and is disabled by default.
- every 60 seconds collect "RegionInfoMetrics", which are the number of storefiles, the storefileSizeMB and memstoreSizeMB. These metrics are queried via HBase's Java-API
- every 600 seconds collect "CompactionMetrics", which are start and stop points of compactions. Those are parsed from the log files of the RegionServers. Right now there is no differentiation between major and minor compactions.
- once a day cleanup the database, which erases data older than one week.