Use median not average document count to determine group coverage

If a group has too many nodes, all others will have less than average.

1 files changed, 89 insertions, 0 deletions

diff --git a/container-search/src/test/java/com/yahoo/search/dispatch/searchcluster/SearchClusterCoverageTest.java b/container-search/src/test/java/com/yahoo/search/dispatch/searchcluster/SearchClusterCoverageTest.java
new file mode 100644
index 00000000000..6338107d4b6
--- /dev/null
+++ b/container-search/src/test/java/com/yahoo/search/dispatch/searchcluster/SearchClusterCoverageTest.java
@@ -0,0 +1,89 @@
+// Copyright Verizon Media. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.search.dispatch.searchcluster;
+
+import org.junit.Test;
+
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertTrue;
+
+/**
+ * @author bratseth
+ */
+public class SearchClusterCoverageTest {
+
+    @Test
+    public void two_groups_equal_docs() {
+        var tester =  new SearchClusterTester(2, 3);
+
+        tester.setDocsPerNode(100, 0);
+        tester.setDocsPerNode(100, 1);
+        tester.pingIterationCompleted();
+        assertTrue(tester.group(0).hasSufficientCoverage());
+        assertTrue(tester.group(1).hasSufficientCoverage());
+    }
+
+    @Test
+    public void two_groups_one_missing_docs() {
+        var tester =  new SearchClusterTester(2, 3);
+
+        tester.setDocsPerNode(100, 0);
+        tester.setDocsPerNode( 70, 1);
+        tester.pingIterationCompleted();
+        assertTrue(tester.group(0).hasSufficientCoverage());
+        assertFalse(tester.group(1).hasSufficientCoverage());
+    }
+
+    @Test
+    public void three_groups_one_missing_docs() {
+        var tester =  new SearchClusterTester(3, 3);
+
+        tester.setDocsPerNode(100, 0);
+        tester.setDocsPerNode( 87, 1);  // min is set to 88 in MockSearchCluster
+        tester.setDocsPerNode(100, 2);
+        tester.pingIterationCompleted();
+        assertTrue(tester.group(0).hasSufficientCoverage());
+        assertFalse(tester.group(1).hasSufficientCoverage());
+        assertTrue(tester.group(2).hasSufficientCoverage());
+    }
+
+    @Test
+    public void three_groups_one_missing_docs_but_too_few() {
+        var tester =  new SearchClusterTester(3, 3);
+
+        tester.setDocsPerNode(100, 0);
+        tester.setDocsPerNode( 89, 1);  // min is set to 88 in MockSearchCluster
+        tester.setDocsPerNode(100, 2);
+        tester.pingIterationCompleted();
+        assertTrue(tester.group(0).hasSufficientCoverage());
+        assertTrue(tester.group(1).hasSufficientCoverage());
+        assertTrue(tester.group(2).hasSufficientCoverage());
+    }
+
+    @Test
+    public void three_groups_one_has_too_many_docs() {
+        var tester =  new SearchClusterTester(3, 3);
+
+        tester.setDocsPerNode(100, 0);
+        tester.setDocsPerNode(150, 1);
+        tester.setDocsPerNode(100, 2);
+        tester.pingIterationCompleted();
+        assertTrue(tester.group(0).hasSufficientCoverage());
+        assertTrue(tester.group(1).hasSufficientCoverage());
+        assertTrue(tester.group(2).hasSufficientCoverage());
+    }
+
+    @Test
+    public void three_groups_one_has_a_node_down() {
+        var tester =  new SearchClusterTester(3, 3);
+
+        tester.setDocsPerNode(100, 0);
+        tester.setDocsPerNode(150, 1);
+        tester.setDocsPerNode(100, 2);
+        tester.setWorking(1, 1, false);
+        tester.pingIterationCompleted();
+        assertTrue(tester.group(0).hasSufficientCoverage());
+        assertFalse(tester.group(1).hasSufficientCoverage());
+        assertTrue(tester.group(2).hasSufficientCoverage());
+    }
+
+}