[FLINK-12987] DescriptiveStatisticsHistogram#getCount does not return the number of elements seen

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 1.6.4, 1.7.2, 1.8.0, 1.9.0
• Fix Version/s: 1.10.0
• Component/s: Runtime / Metrics
• Labels: pull-request-available
• Assignee: Nico Kruber
• Reporter: Nico Kruber
• Created: 25/Jun/19 20:28
• Updated: 15/Aug/19 23:03
• Resolved: 15/Aug/19 23:03

Description

DescriptiveStatisticsHistogram#getCount() returns the number of elements in the current window and not the number of total elements seen over time. In contrast, DropwizardHistogramWrapper does this correctly.

We should unify the behaviour and add a unit test for it (there is no generic histogram test yet).

Issue Links

• links to: GitHub Pull Request #8886