Add cancellation framework changes in wlm

CHANGELOG.md

@@ -12,6 +12,7 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 - [Remote Publication] Upload incremental cluster state on master re-election ([#15145](https://github.com/opensearch-project/OpenSearch/pull/15145))
 - Making _cat/allocation API use indexLevelStats ([#15292](https://github.com/opensearch-project/OpenSearch/pull/15292))
 - Memory optimisations in _cluster/health API ([#15492](https://github.com/opensearch-project/OpenSearch/pull/15492))
+- [Workload Management] QueryGroup resource cancellation framework changes ([#15651](https://github.com/opensearch-project/OpenSearch/pull/15651))
 
 ### Dependencies
 - Bump `com.azure:azure-identity` from 1.13.0 to 1.13.2 ([#15578](https://github.com/opensearch-project/OpenSearch/pull/15578))

server/src/main/java/org/opensearch/cluster/metadata/QueryGroup.java

@@ -12,6 +12,7 @@
 import org.opensearch.cluster.Diff;
 import org.opensearch.common.UUIDs;
 import org.opensearch.common.annotation.ExperimentalApi;
+import org.opensearch.common.annotation.PublicApi;
 import org.opensearch.core.common.io.stream.StreamInput;
 import org.opensearch.core.common.io.stream.StreamOutput;
 import org.opensearch.core.xcontent.ToXContentObject;
@@ -41,7 +42,7 @@
  *              "updated_at": 4513232415
  * }
  */
-@ExperimentalApi
+@PublicApi(since = "2.18.0")
 public class QueryGroup extends AbstractDiffable<QueryGroup> implements ToXContentObject {
 
     public static final String _ID_STRING = "_id";

server/src/main/java/org/opensearch/wlm/QueryGroupLevelResourceUsageView.java

@@ -8,8 +8,6 @@
 
 package org.opensearch.wlm;
 
-import org.opensearch.tasks.Task;
-
 import java.util.List;
 import java.util.Map;
 
@@ -20,11 +18,11 @@
  */
 public class QueryGroupLevelResourceUsageView {
     // resourceUsage holds the resource usage data for a QueryGroup at a point in time
-    private final Map<ResourceType, Long> resourceUsage;
+    private final Map<ResourceType, Double> resourceUsage;
     // activeTasks holds the list of active tasks for a QueryGroup at a point in time
-    private final List<Task> activeTasks;
+    private final List<QueryGroupTask> activeTasks;
 
-    public QueryGroupLevelResourceUsageView(Map<ResourceType, Long> resourceUsage, List<Task> activeTasks) {
+    public QueryGroupLevelResourceUsageView(Map<ResourceType, Double> resourceUsage, List<QueryGroupTask> activeTasks) {
         this.resourceUsage = resourceUsage;
         this.activeTasks = activeTasks;
     }
@@ -34,7 +32,7 @@ public QueryGroupLevelResourceUsageView(Map<ResourceType, Long> resourceUsage, L
      *
      * @return The map of resource usage data
      */
-    public Map<ResourceType, Long> getResourceUsageData() {
+    public Map<ResourceType, Double> getResourceUsageData() {
         return resourceUsage;
     }
 
@@ -43,7 +41,7 @@ public Map<ResourceType, Long> getResourceUsageData() {
      *
      * @return The list of active tasks
      */
-    public List<Task> getActiveTasks() {
+    public List<QueryGroupTask> getActiveTasks() {
         return activeTasks;
     }
 }

server/src/main/java/org/opensearch/wlm/QueryGroupTask.java

@@ -10,29 +10,33 @@
 
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
+import org.opensearch.common.annotation.PublicApi;
 import org.opensearch.common.unit.TimeValue;
 import org.opensearch.common.util.concurrent.ThreadContext;
 import org.opensearch.core.tasks.TaskId;
 import org.opensearch.tasks.CancellableTask;
 
 import java.util.Map;
 import java.util.Optional;
+import java.util.function.LongSupplier;
 import java.util.function.Supplier;
 
 import static org.opensearch.search.SearchService.NO_TIMEOUT;
 
 /**
  * Base class to define QueryGroup tasks
  */
+@PublicApi(since = "2.18.0")
 public class QueryGroupTask extends CancellableTask {
 
     private static final Logger logger = LogManager.getLogger(QueryGroupTask.class);
     public static final String QUERY_GROUP_ID_HEADER = "queryGroupId";
     public static final Supplier<String> DEFAULT_QUERY_GROUP_ID_SUPPLIER = () -> "DEFAULT_QUERY_GROUP";
+    private final LongSupplier nanoTimeSupplier;
     private String queryGroupId;
 
     public QueryGroupTask(long id, String type, String action, String description, TaskId parentTaskId, Map<String, String> headers) {
-        this(id, type, action, description, parentTaskId, headers, NO_TIMEOUT);
+        this(id, type, action, description, parentTaskId, headers, NO_TIMEOUT, System::nanoTime);
     }
 
     public QueryGroupTask(
@@ -43,8 +47,22 @@ public QueryGroupTask(
         TaskId parentTaskId,
         Map<String, String> headers,
         TimeValue cancelAfterTimeInterval
+    ) {
+        this(id, type, action, description, parentTaskId, headers, cancelAfterTimeInterval, System::nanoTime);
+    }
+
+    public QueryGroupTask(
+        long id,
+        String type,
+        String action,
+        String description,
+        TaskId parentTaskId,
+        Map<String, String> headers,
+        TimeValue cancelAfterTimeInterval,
+        LongSupplier nanoTimeSupplier
     ) {
         super(id, type, action, description, parentTaskId, headers, cancelAfterTimeInterval);
+        this.nanoTimeSupplier = nanoTimeSupplier;
     }
 
     /**
@@ -69,6 +87,10 @@ public final void setQueryGroupId(final ThreadContext threadContext) {
             .orElse(DEFAULT_QUERY_GROUP_ID_SUPPLIER.get());
     }
 
+    public long getElapsedTime() {
+        return nanoTimeSupplier.getAsLong() - getStartTimeNanos();
+    }
+
     @Override
     public boolean shouldCancelChildrenOnCancellation() {
         return false;

server/src/main/java/org/opensearch/wlm/ResourceType.java

@@ -10,8 +10,9 @@
 
 import org.opensearch.common.annotation.PublicApi;
 import org.opensearch.core.common.io.stream.StreamOutput;
-import org.opensearch.core.tasks.resourcetracker.ResourceStats;
-import org.opensearch.tasks.Task;
+import org.opensearch.wlm.tracker.CpuUsageCalculator;
+import org.opensearch.wlm.tracker.MemoryUsageCalculator;
+import org.opensearch.wlm.tracker.ResourceUsageCalculator;
 
 import java.io.IOException;
 import java.util.List;
@@ -24,19 +25,25 @@
  */
 @PublicApi(since = "2.17.0")
 public enum ResourceType {
-    CPU("cpu", task -> task.getTotalResourceUtilization(ResourceStats.CPU), true),
-    MEMORY("memory", task -> task.getTotalResourceUtilization(ResourceStats.MEMORY), true);
+    CPU("cpu", true, CpuUsageCalculator.INSTANCE, WorkloadManagementSettings::getNodeLevelCpuCancellationThreshold),
+    MEMORY("memory", true, MemoryUsageCalculator.INSTANCE, WorkloadManagementSettings::getNodeLevelMemoryCancellationThreshold);
 
     private final String name;
-    private final Function<Task, Long> getResourceUsage;
     private final boolean statsEnabled;
-
+    private final ResourceUsageCalculator resourceUsageCalculator;
+    private final Function<WorkloadManagementSettings, Double> nodeLevelThresholdSupplier;
     private static List<ResourceType> sortedValues = List.of(CPU, MEMORY);
 
-    ResourceType(String name, Function<Task, Long> getResourceUsage, boolean statsEnabled) {
+    ResourceType(
+        String name,
+        boolean statsEnabled,
+        ResourceUsageCalculator resourceUsageCalculator,
+        Function<WorkloadManagementSettings, Double> nodeLevelThresholdSupplier
+    ) {
         this.name = name;
-        this.getResourceUsage = getResourceUsage;
         this.statsEnabled = statsEnabled;
+        this.resourceUsageCalculator = resourceUsageCalculator;
+        this.nodeLevelThresholdSupplier = nodeLevelThresholdSupplier;
     }
 
     /**
@@ -61,20 +68,18 @@ public String getName() {
         return name;
     }
 
-    /**
-     * Gets the resource usage for a given resource type and task.
-     *
-     * @param task the task for which to calculate resource usage
-     * @return the resource usage
-     */
-    public long getResourceUsage(Task task) {
-        return getResourceUsage.apply(task);
-    }
-
     public boolean hasStatsEnabled() {
         return statsEnabled;
     }
 
+    public ResourceUsageCalculator getResourceUsageCalculator() {
+        return resourceUsageCalculator;
+    }
+
+    public double getNodeLevelThreshold(WorkloadManagementSettings settings) {
+        return nodeLevelThresholdSupplier.apply(settings);
+    }
+
     public static List<ResourceType> getSortedValues() {
         return sortedValues;
     }

server/src/main/java/org/opensearch/wlm/WorkloadManagementSettings.java

@@ -8,13 +8,15 @@
 
 package org.opensearch.wlm;
 
+import org.opensearch.common.annotation.PublicApi;
 import org.opensearch.common.settings.ClusterSettings;
 import org.opensearch.common.settings.Setting;
 import org.opensearch.common.settings.Settings;
 
 /**
  * Main class to declare Workload Management related settings
  */
+@PublicApi(since = "2.18.0")
 public class WorkloadManagementSettings {
     private static final Double DEFAULT_NODE_LEVEL_MEMORY_REJECTION_THRESHOLD = 0.8;
     private static final Double DEFAULT_NODE_LEVEL_MEMORY_CANCELLATION_THRESHOLD = 0.9;

server/src/main/java/org/opensearch/wlm/cancellation/MaximumResourceTaskSelectionStrategy.java

@@ -0,0 +1,71 @@
+/*
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * The OpenSearch Contributors require contributions made to
+ * this file be licensed under the Apache-2.0 license or a
+ * compatible open source license.
+ */
+
+package org.opensearch.wlm.cancellation;
+
+import org.opensearch.wlm.QueryGroupTask;
+import org.opensearch.wlm.ResourceType;
+
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.Comparator;
+import java.util.List;
+import java.util.stream.Collectors;
+
+import static org.opensearch.wlm.cancellation.QueryGroupTaskCancellationService.MIN_VALUE;
+
+/**
+ * Represents the highest resource consuming task first selection strategy.
+ */
+public class MaximumResourceTaskSelectionStrategy implements TaskSelectionStrategy {
+
+    public MaximumResourceTaskSelectionStrategy() {}
+
+    /**
+     * Returns a comparator that defines the sorting condition for tasks.
+     * This is the default implementation since the most resource consuming tasks are the likely to regress the performance.
+     * from resiliency point of view it makes sense to cancel them first
+     *
+     * @return The comparator
+     */
+    private Comparator<QueryGroupTask> sortingCondition(ResourceType resourceType) {
+        return Comparator.comparingDouble(task -> resourceType.getResourceUsageCalculator().calculateTaskResourceUsage(task));
+    }
+
+    /**
+     * Selects tasks for cancellation based on the provided limit and resource type.
+     * The tasks are sorted based on the sorting condition and then selected until the accumulated resource usage reaches the limit.
+     *
+     * @param tasks The list of tasks from which to select
+     * @param limit The limit on the accumulated resource usage
+     * @param resourceType The type of resource to consider
+     * @return The list of selected tasks
+     * @throws IllegalArgumentException If the limit is less than zero
+     */
+    public List<QueryGroupTask> selectTasksForCancellation(List<QueryGroupTask> tasks, double limit, ResourceType resourceType) {
+        if (limit < 0) {
+            throw new IllegalArgumentException("limit has to be greater than zero");
+        }
+        if (limit < MIN_VALUE) {
+            return Collections.emptyList();
+        }
+
+        List<QueryGroupTask> sortedTasks = tasks.stream().sorted(sortingCondition(resourceType).reversed()).collect(Collectors.toList());
+
+        List<QueryGroupTask> selectedTasks = new ArrayList<>();
+        double accumulated = 0;
+        for (QueryGroupTask task : sortedTasks) {
+            selectedTasks.add(task);
+            accumulated += resourceType.getResourceUsageCalculator().calculateTaskResourceUsage(task);
+            if ((accumulated - limit) > MIN_VALUE) {
+                break;
+            }
+        }
+        return selectedTasks;
+    }
+}