[BUG] org.opensearch.script.expression.MoreExpressionIT.testSpecialValueVariable {p0={"search.concurrent_segment_search.enabled":"true"}} is flaky

[reta]

Describe the bug
The test case org.opensearch.script.expression.MoreExpressionIT.testSpecialValueVariable {p0={"search.concurrent_segment_search.enabled":"true"}} is flaky:

org.opensearch.script.expression.MoreExpressionIT.testSpecialValueVariable {p0={"search.concurrent_segment_search.enabled":"true"}}

java.lang.AssertionError: expected:<15.0> but was:<30.0>
	at __randomizedtesting.SeedInfo.seed([F1394EDB559EDD27:B970EFC671A78493]:0)
	at org.junit.Assert.fail(Assert.java:89)
	at org.junit.Assert.failNotEquals(Assert.java:835)
	at org.junit.Assert.assertEquals(Assert.java:555)
	at org.junit.Assert.assertEquals(Assert.java:685)
	at org.opensearch.script.expression.MoreExpressionIT.testSpecialValueVariable(MoreExpressionIT.java:540)
	at java.base/jdk.internal.reflect.DirectMethodHandleAccessor.invoke(DirectMethodHandleAccessor.java:104)
	at java.base/java.lang.reflect.Method.invoke(Method.java:578)
	at com.carrotsearch.randomizedtesting.RandomizedRunner.invoke(RandomizedRunner.java:1750)
	at com.carrotsearch.randomizedtesting.RandomizedRunner$8.evaluate(RandomizedRunner.java:938)
	at com.carrotsearch.randomizedtesting.RandomizedRunner$9.evaluate(RandomizedRunner.java:974)
	at com.carrotsearch.randomizedtesting.RandomizedRunner$10.evaluate(RandomizedRunner.java:988)
	at com.carrotsearch.randomizedtesting.rules.StatementAdapter.evaluate(StatementAdapter.java:36)
	at org.junit.rules.RunRules.evaluate(RunRules.java:20)
	at org.apache.lucene.tests.util.TestRuleSetupTeardownChained$1.evaluate(TestRuleSetupTeardownChained.java:48)
	at org.apache.lucene.tests.util.AbstractBeforeAfterRule$1.evaluate(AbstractBeforeAfterRule.java:43)
	at org.apache.lucene.tests.util.TestRuleThreadAndTestName$1.evaluate(TestRuleThreadAndTestName.java:45)
	at org.apache.lucene.tests.util.TestRuleIgnoreAfterMaxFailures$1.evaluate(TestRuleIgnoreAfterMaxFailures.java:60)
	at org.apache.lucene.tests.util.TestRuleMarkFailure$1.evaluate(TestRuleMarkFailure.java:44)
	at org.junit.rules.RunRules.evaluate(RunRules.java:20)
	at com.carrotsearch.randomizedtesting.rules.StatementAdapter.evaluate(StatementAdapter.java:36)
	at com.carrotsearch.randomizedtesting.ThreadLeakControl$StatementRunner.run(ThreadLeakControl.java:368)
	at com.carrotsearch.randomizedtesting.ThreadLeakControl.forkTimeoutingTask(ThreadLeakControl.java:817)
	at com.carrotsearch.randomizedtesting.ThreadLeakControl$3.evaluate(ThreadLeakControl.java:468)
	at com.carrotsearch.randomizedtesting.RandomizedRunner.runSingleTest(RandomizedRunner.java:947)
	at com.carrotsearch.randomizedtesting.RandomizedRunner$5.evaluate(RandomizedRunner.java:832)
	at com.carrotsearch.randomizedtesting.RandomizedRunner$6.evaluate(RandomizedRunner.java:883)
	at com.carrotsearch.randomizedtesting.RandomizedRunner$7.evaluate(RandomizedRunner.java:894)

To Reproduce

./gradlew ':modules:lang-expression:internalClusterTest' --tests "org.opensearch.script.expression.MoreExpressionIT" -Dtests.method="testSpecialValueVariable {p0={"search.concurrent_segment_search.enabled":"true"}}" -Dtests.seed=F1394EDB559EDD27

Expected behavior
Test must always pass

Plugins
Standard

Screenshots
If applicable, add screenshots to help explain your problem.

Host/Environment (please complete the following information):

• CI

Additional context
https://build.ci.opensearch.org/job/gradle-check/25705

[reta]

CC @sohami @neetikasinghal fyi :(

[andrross]

I can get this to fail deterministically with the following:

./gradlew ':modules:lang-expression:internalClusterTest' --tests 'org.opensearch.script.expression.MoreExpressionIT' -Dtests.seed=8D2B659F15124742

It only fails when concurrent search is enabled.