Java

Setup

The following are the two popular exporters for Java JVM Metrics JMX Exporter or Micrometer Prometheus Exporter. The Micrometer exporter provides more information and is the recommended option.

Metrics and Key Performance Indicators (KPI)s

Metric	KPI
GC Count jvm_gc_pause_seconds_count	Rate of GC Count rate(jvm_gc_pause_seconds_count{action="end of major GC"}[2m])
GC Pause Time jvm_gc_pause_seconds_sum	Rate of GC Pause Time rate(jvm_gc_pause_seconds_sum{action="end of major GC"}[2m])
Live Thread Count jvm_threads_live_threads	Live thread count normalized against a threshold jvm_threads_live_threads / 200

Alerts

KPI	Alert
Rate of GC Count	JvmMajorGCCountHigh
Rate of GC Pause Time	JvmMajorGCTimeHigh
Live Thread Count	Saturation on jvm:live_threads

Dashboard

CPU

• system_cpu_usage

• process_cpu_usage

• system_cpu_count

• system_load_average_1m

Heap Memory

The following heap metrics are available for Eden Space, Survivor Space and Tenured Generation

• jvm_memory_used_bytes{area="heap"}

• jvm_memory_committed_bytes{area="heap"}

• jvm_memory_max_bytes{area="heap"}

Non Heap Memory

The following non heap metrics are available for Metaspace, Compressed Class Space and Code Cache

• jvm_memory_used_bytes{area="nonheap"}

• jvm_memory_committed_bytes{area="nonheap"}

• jvm_memory_max_bytes{area="nonheap"}

Buffer Pools

The following metrics are available for Direct and Mapped buffers

• jvm_buffer_total_capacity_bytes

• jvm_buffer_memory_used_bytes

• jvm_buffer_count_buffers

Threads

• jvm_threads_live_threads

• jvm_threads_daemon_threads

• jvm_threads_peak_threads

• process_threads

• jvm_threads_states_threads

File Descriptors

• process_files_open_files

• process_files_max_files

Classes Loaded

• jvm_classes_loaded_classes