Metrics for gl_jvm_memory_total_max and gl_jvm_memory_non_heap_max show unlimited in 6.0 where they previously showed the configured max in 5.2

When using the metrics exporter for graylog, the behavior of the following metrics has changed between Graylog 5.2 and 6.0:

gl_jvm_memory_total_max
gl_jvm_memory_non_heap_max

In Graylog 5.2 these displayed the configured max value for JVM heap. In Graylog 6.0 they show -1 or unlimited:

Its not clear to me which of these is the correct value to return though.

Expected Behavior

Current Behavior

Possible Solution

Steps to Reproduce (for bugs)

Configure metric exporting via server.conf

prometheus_exporter_enabled = true
prometheus_exporter_bind_address = 0.0.0.0:9833
prometheus_exporter_mapping_file_path_custom = /usr/share/graylog-server/prometheus-exporter-mapping-custom.yml

Relevant metrics declared in prometheus-exporter-mapping-custom.yml

metric_mappings:
  - metric_name: "jvm_memory_total_max"
    match_pattern: "jvm.memory.total.max"
  - metric_name: "jvm_memory_non_heap_max"
    match_pattern: "jvm.memory.non-heap.max"

view metric via :9833

Context

Your Environment

Graylog Version: 6.0.3
Java Version: Bundled
OpenSearch Version: 2.15.0
MongoDB Version: 6.0.16
Operating System: Ubuntu Server 22.04 LTS
Browser version: Google Chrome Version 126.0.6478.127 (Official Build) (arm64)

Graylog2 / graylog2-server