[OPENNLP-1472] Fix flaky (sub-) test of GradientDescentUtilsTest in sandbox component 'nlp-utils'

• Type: Test
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 2.1.1
• Fix Version/s: 2.2.0
• External issue URL: https://github.com/apache/opennlp-sandbox/pull/88
• Assignee: Martin Wiesner
• Reporter: Martin Wiesner
• Created: 20/Feb/23 12:37
• Updated: 22/Apr/23 17:39
• Resolved: 25/Feb/23 22:07

Description

A flaky test has been discovered with recent modernizations of the sandbox components. It lives in 'nlp-utils' and the problem signals a fragile test setup or potentially numerical instabilities:

Error: org.apache.opennlp.utils.regression.GradientDescentUtilsTest.testConvergence Time elapsed: 1.156 s <<< ERROR!
3270java.lang.RuntimeException: failed to converge at iteration 75129 with cost going from 5.010577258277822 to 5.010577258277823
3271 at org.apache.opennlp.utils.regression.GradientDescentUtilsTest.testConvergence(GradientDescentUtilsTest.java:34)

The problem (sometimes) occurs on different platforms / environments (Win, Lin, Mac).

Aims:

• Investigate the cause of the flakyness
• Fix the test (environment / setup) so it runs reliably.