[
https://issues.apache.org/jira/browse/KAFKA-17954?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17896110#comment-17896110
]
Matthias J. Sax commented on KAFKA-17954:
-----------------------------------------
Seem it would be simple to change from `null` to `0` (or `-1`) ?
> Error getting oldest-iterator-open-since-ms from JMX
> ----------------------------------------------------
>
> Key: KAFKA-17954
> URL: https://issues.apache.org/jira/browse/KAFKA-17954
> Project: Kafka
> Issue Type: Bug
> Components: streams
> Affects Versions: 3.8.1
> Reporter: Nicholas Telford
> Assignee: Nicholas Telford
> Priority: Minor
>
> In
> [KIP-989|https://cwiki.apache.org/confluence/display/KAFKA/KIP-989%3A+Improved+StateStore+Iterator+metrics+for+detecting+leaks]
> we introduced a new metric, {{{}oldest-iterator-open-since-ms{}}}, which
> reports the timestamp that the oldest currently open KeyValueIterator was
> opened at.
> However, if no iterators are currently open, this Gauge returns {{{}null{}}}.
> When using the Prometheus {{JmxScraper}} to scrape this metric, its value is
> added to a {{{}ConcurrentHashMap{}}}, which does _not_ permit {{null}} values.
> Consequently, on-scrape, we see this {{WARN}} log message:
> {noformat}
> Error getting JMX attribute 'oldest-iterator-open-since-ms' {noformat}
> We should find some other way to report the absence of this metric that does
> not cause problems with {{{}ConcurrentHashMap{}}}.
--
This message was sent by Atlassian Jira
(v8.20.10#820010)
