Semantic Conventions for Runtime Environment Metrics
Status: Experimental
This document includes semantic conventions for runtime environment level metrics in OpenTelemetry. Also consider the general metric, system metrics and OS Process metrics semantic conventions when instrumenting runtime environments.
Metric Instruments
Runtime environments vary widely in their terminology, implementation, and relative values for a given metric. For example, Go and Python are both garbage collected languages, but comparing heap usage between the Go and CPython runtimes directly is not meaningful. For this reason, this document does not propose any standard top-level runtime metric instruments. See OTEP 108 for additional discussion.
Runtime Environment Specific Metrics - process.runtime.{environment}.
Metrics specific to a certain runtime environment should be prefixed with
process.runtime.{environment}. and follow the semantic conventions outlined in
general metric semantic
conventions. Authors of
runtime instrumentations are responsible for the choice of {environment} to
avoid ambiguity when interpreting a metric’s name or values.
For example, some programming languages have multiple runtime environments
that vary significantly in their implementation, like Python which has many
implementations. For
such languages, consider using specific {environment} prefixes to avoid
ambiguity, like process.runtime.cpython. and process.runtime.pypy..
There are other dimensions even within a given runtime environment to consider, for example pthreads vs green thread implementations.
Attributes
process.runtime resource attributes SHOULD be included on runtime metric events as appropriate.
JVM Metrics
Description: Java Virtual Machine (JVM) metrics captured under process.runtime.jvm.
All JVM metric attributes are required unless otherwise indicated.
| Name | Description | Unit | Unit (UCUM) | Instrument Type (*) | Value Type | Attribute Key | Attribute Values |
|---|---|---|---|---|---|---|---|
| process.runtime.jvm.memory.usage | Measure of memory used | Bytes | By | UpDownCounter | Int64 | type | "heap", "nonheap" |
| pool | Name of pool [1] | ||||||
| process.runtime.jvm.memory.init | Measure of initial memory requested | Bytes | By | UpDownCounter | Int64 | type | "heap", "nonheap" |
| pool | Name of pool [1] | ||||||
| process.runtime.jvm.memory.committed | Measure of memory committed | Bytes | By | UpDownCounter | Int64 | type | "heap", "nonheap" |
| pool | Name of pool [1] | ||||||
| process.runtime.jvm.memory.limit | Measure of max obtainable memory | Bytes | By | UpDownCounter | Int64 | type | "heap", "nonheap" |
| pool | Name of pool [1] | ||||||
| process.runtime.jvm.threads.count | Number of executing threads | threads | {threads} | UpDownCounter | Int64 | ||
| process.runtime.jvm.classes.loaded | Number of classes loaded since JVM start | classes | {classes} | Counter | Int64 | ||
| process.runtime.jvm.classes.unloaded | Number of classes unloaded since JVM start | classes | {classes} | Counter | Int64 | ||
| process.runtime.jvm.classes.current_loaded | Number of classes currently loaded | classes | {classes} | UpDownCounter | Int64 | ||
| process.runtime.jvm.cpu.utilization | Recent cpu utilization for the process [2] | 1 | 1 | Asynchronous Gauge | Double | ||
| process.runtime.jvm.system.cpu.utilization | Recent cpu utilization for the whole system [2] | 1 | 1 | Asynchronous Gauge | Double | ||
| process.runtime.jvm.system.cpu.load_1m | Average CPU load of the whole system for the last minute | 1 | 1 | Asynchronous Gauge | Double | ||
| process.runtime.jvm.buffer.usage | Measure of memory used by buffers | Bytes | By | UpDownCounter | Int64 | pool | Name of pool[3] |
| process.runtime.jvm.buffer.limit | Measure of total memory capacity of buffers | Bytes | By | UpDownCounter | Int64 | pool | Name of pool[3] |
| process.runtime.jvm.buffer.count | Number of buffers in the pool | buffers | {buffers} | UpDownCounter | Int64 | pool | Name of pool[3] |
[1]: Pool names are generally obtained via MemoryPoolMXBean#getName().
Examples include G1 Old Gen, G1 Eden space, G1 Survivor Space, Metaspace, etc.
[2]: These utilizations are not defined as being for the specific interval since last measurement (unlike system.cpu.utilization).
[3]: Pool names are generally obtained via BufferPoolMXBean#getName().