[KUDU-3549] String gauge exposed in prometheus format

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 1.17.0
• Fix Version/s: 1.18.0, 1.17.1
• Component/s: metrics
• Code Review: https://gerrit.cloudera.org/#/c/20990/
• Assignee: Alexey Serbin
• Reporter: YUBI LEE
• Created: 31/Jan/24 01:53
• Updated: 07/Feb/24 22:11
• Resolved: 07/Feb/24 17:32

Description

According to KUDU-3375, "Kudu now exposes all its metrics except for string gauges in Prometheus format via the embedded webserver's `/metrics_prometheus` endpoint".

 

• https://github.com/apache/kudu/blob/89e2715faf96afe0b67482166fda9c8699e8052f/docs/prior_release_notes.adoc?plain=1#L143-L145
• https://issues.apache.org/jira/browse/KUDU-3375

 

However, with this commit (https://github.com/apache/kudu/commit/e65ea38a4860c007d93ada9c991bccec903a80b1) , string gauge related to clock_ntp_status is exposed.

 

# HELP kudu_master_clock_ntp_status Output of ntp_adjtime()/ntp_gettime() kernel API call
# TYPE kudu_master_clock_ntp_status gauge
kudu_master_clock_ntp_status{unit_type="state"} now:1706665936956760 maxerror:70013 status:ok 

It prevents prometheus operators from collecting prometheus metrics for kudu.