add testing for generated metrics

i.e. added testing for calculateSchedLatency

Signed-off-by: Kartavya Vashishtha <[email protected]>

src/main/java/org/opensearch/performanceanalyzer/commons/os/ThreadSched.java

@@ -10,6 +10,7 @@
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
+import java.util.Objects;
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
 import org.apache.logging.log4j.message.ParameterizedMessage;
@@ -38,6 +39,27 @@ public static class SchedMetrics {
             this.contextSwitchRate = contextSwitchRate;
         }
 
+        @Override
+        public int hashCode() {
+            return Objects.hash(this.avgRuntime, this.avgWaittime, this.contextSwitchRate);
+        }
+
+        @Override
+        public boolean equals(Object o) {
+            if (this == o) {
+                return true;
+            }
+            if (o == null || getClass() != o.getClass()) {
+                return false;
+            }
+
+            SchedMetrics other = (SchedMetrics) o;
+
+            return Double.compare(avgRuntime, other.avgRuntime) == 0
+                    && Double.compare(avgWaittime, other.avgWaittime) == 0
+                    && Double.compare(contextSwitchRate, other.contextSwitchRate) == 0;
+        }
+
         @Override
         public String toString() {
             return new StringBuilder()

src/test/java/org/opensearch/performanceanalyzer/commons/os/ThreadSchedTests.java

@@ -8,13 +8,14 @@
 import static org.junit.Assert.assertEquals;
 import static org.mockito.ArgumentMatchers.eq;
 import static org.mockito.ArgumentMatchers.isA;
+import static org.mockito.Mockito.verify;
 
 import java.util.List;
 import java.util.Map;
-import org.junit.Before;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.mockito.Mockito;
+import org.opensearch.performanceanalyzer.commons.metrics_generator.linux.LinuxSchedMetricsGenerator;
 import org.powermock.api.mockito.PowerMockito;
 import org.powermock.core.classloader.annotations.PowerMockIgnore;
 import org.powermock.core.classloader.annotations.PrepareForTest;
@@ -30,25 +31,61 @@ public class ThreadSchedTests {
 
     private Map<String, Map<String, Object>> tidKVMap =
             Map.of(
-                    "1", Map.of("runticks", "1", "waitticks", "2", "totctxsws", "3"),
-                    "2", Map.of("runticks", "4", "waitticks", "5", "totctxsws", "6"),
-                    "3", Map.of("runticks", "7", "waitticks", "8", "totctxsws", "9"));
+                    "1", Map.of("runticks", 100000000L, "waitticks", 100000000L, "totctxsws", 100L),
+                    "2", Map.of("runticks", 100000000L, "waitticks", 100000000L, "totctxsws", 10L),
+                    "3",
+                            Map.of(
+                                    "runticks",
+                                    500000000L,
+                                    "waitticks",
+                                    500000000L,
+                                    "totctxsws",
+                                    120L));
+
+    private Map<String, Map<String, Object>> nextTidKVMap =
+            Map.of(
+                    "1", Map.of("runticks", 200000000L, "waitticks", 200000000L, "totctxsws", 200L),
+                    "2", Map.of("runticks", 500000000L, "waitticks", 500000000L, "totctxsws", 20L),
+                    "3",
+                            Map.of(
+                                    "runticks",
+                                    700000000L,
+                                    "waitticks",
+                                    700000000L,
+                                    "totctxsws",
+                                    220L));
+
+    @Test
+    public void testMetrics() throws Exception {
+        // this test checks that
+        // 1. ThreadSched calls the SchemaFileParser constructor with the correct path
+        // 2. ThreadSched calculates the correct metrics from procfile data
 
-    @Before
-    public void setUp() throws Exception {
         // mock OSGlobals
         PowerMockito.mockStatic(OSGlobals.class);
         PowerMockito.when(OSGlobals.getPid()).thenReturn("0");
         PowerMockito.when(OSGlobals.getTids()).thenReturn(List.of("1", "2", "3"));
-    }
 
-    @Test
-    public void testMetrics() throws Exception {
+        // mock System.currentTimeMillis()
+        // used by ThreadSched to compute SchedMetric
+        PowerMockito.mockStatic(System.class);
+        // having the time difference = 1000ms
+        // means that contextSwitchRate = difference in totctxsws
+        PowerMockito.when(System.currentTimeMillis()).thenReturn(10L, 1010L);
+
+        // mock the metrics generator used by ThreadSched
+        LinuxSchedMetricsGenerator linuxSchedMetricsGenerator =
+                Mockito.mock(LinuxSchedMetricsGenerator.class);
+        PowerMockito.whenNew(LinuxSchedMetricsGenerator.class)
+                .withNoArguments()
+                .thenReturn(linuxSchedMetricsGenerator);
+
         // mock SchemaFileParser (used by ThreadSched to read procfiles)
         SchemaFileParser schemaFileParser = Mockito.mock(SchemaFileParser.class);
 
         PowerMockito.when(schemaFileParser.parse())
-                .thenReturn(tidKVMap.get("1"), tidKVMap.get("2"), tidKVMap.get("3"));
+                .thenReturn(tidKVMap.get("1"), tidKVMap.get("2"), tidKVMap.get("3"))
+                .thenReturn(nextTidKVMap.get("1"), nextTidKVMap.get("2"), nextTidKVMap.get("3"));
 
         PowerMockito.whenNew(SchemaFileParser.class)
                 .withAnyArguments()
@@ -75,5 +112,15 @@ public void testMetrics() throws Exception {
                         isA(SchemaFileParser.FieldTypes[].class));
 
         assertEquals(tidKVMap, ThreadSched.INSTANCE.getTidKVMap());
+
+        ThreadSched.INSTANCE.addSample();
+
+        // verify that the metrics generator is given correct metrics
+        verify(linuxSchedMetricsGenerator)
+                .setSchedMetric("1", new ThreadSched.SchedMetrics(0.001, 0.001, 100.0));
+        verify(linuxSchedMetricsGenerator)
+                .setSchedMetric("2", new ThreadSched.SchedMetrics(0.04, 0.04, 10.0));
+        verify(linuxSchedMetricsGenerator)
+                .setSchedMetric("3", new ThreadSched.SchedMetrics(0.002, 0.002, 100.0));
     }
 }