redis · ggivo · Feb 11, 2026 · Feb 11, 2026 · Feb 11, 2026 · Feb 11, 2026
diff --git a/Makefile b/Makefile
@@ -2,7 +2,7 @@ PATH := ./redis-git/src:${PATH}
 
 # Supported test env versions
 SUPPORTED_TEST_ENV_VERSIONS := 8.6 8.4 8.2 8.0 7.4 7.2 6.2
-DEFAULT_TEST_ENV_VERSION := 8.4
+DEFAULT_TEST_ENV_VERSION := 8.6
 REDIS_ENV_WORK_DIR := $(or ${REDIS_ENV_WORK_DIR},/tmp/redis-env-work)
 CLIENT_LIBS_TEST_IMAGE := redislabs/client-libs-test:8.2.2
 TOXIPROXY_IMAGE := ghcr.io/shopify/toxiproxy:2.8.0

diff --git a/src/main/java/redis/clients/jedis/resps/HotkeysInfo.java b/src/main/java/redis/clients/jedis/resps/HotkeysInfo.java
@@ -23,7 +23,7 @@ public class HotkeysInfo implements Serializable {
   public static final String TRACKING_ACTIVE = "tracking-active";
   public static final String SAMPLE_RATIO = "sample-ratio";
   public static final String SELECTED_SLOTS = "selected-slots";
-  public static final String SAMPLED_COMMAND_SELECTED_SLOTS_US = "sampled-command-selected-slots-us";
+  public static final String SAMPLED_COMMANDS_SELECTED_SLOTS_US = "sampled-commands-selected-slots-us";
   public static final String ALL_COMMANDS_SELECTED_SLOTS_US = "all-commands-selected-slots-us";
   public static final String ALL_COMMANDS_ALL_SLOTS_US = "all-commands-all-slots-us";
   public static final String NET_BYTES_SAMPLED_COMMANDS_SELECTED_SLOTS = "net-bytes-sampled-commands-selected-slots";
@@ -88,9 +88,12 @@ public long getSampleRatio() {
   }
 
   /**
-   * Returns the selected slot ranges. Each element is an int array of [start, end] representing a
-   * slot range (inclusive).
-   * @return list of slot ranges, empty if all slots are selected
+   * Returns the selected slots. Each element is an int array that can be:
+   * <ul>
+   * <li>A single slot: {@code [slot]} (array with 1 element)</li>
+   * <li>A slot range: {@code [start, end]} (array with 2 elements, inclusive)</li>
+   * </ul>
+   * @return list of slot entries, empty if all slots are selected
    */
   public List<int[]> getSelectedSlots() {
     return selectedSlots;
@@ -172,8 +175,12 @@ private static Map<String, Long> parseKeyValueMap(Object data) {
   }
 
   /**
-   * Parse selected-slots which is an array of [start, end] ranges. Example: [[0, 16383]] means all
-   * slots.
+   * Parse selected-slots which is an array of slot entries. Each entry can be:
+   * <ul>
+   * <li>A single slot: [slot] (array with 1 element)</li>
+   * <li>A slot range: [start, end] (array with 2 elements)</li>
+   * </ul>
+   * Example: [[0, 2], [100]] means slots 0-2 (range) and slot 100 (single).
    */
   @SuppressWarnings("unchecked")
   private static List<int[]> parseSlotRanges(Object data) {
@@ -188,7 +195,12 @@ private static List<int[]> parseSlotRanges(Object data) {
     for (Object item : list) {
       if (item instanceof List) {
         List<?> range = (List<?>) item;
-        if (range.size() == 2) {
+        if (range.size() == 1) {
+          // Single slot
+          int slot = LONG.build(range.get(0)).intValue();
+          result.add(new int[] { slot });
+        } else if (range.size() == 2) {
+          // Slot range
           int start = LONG.build(range.get(0)).intValue();
           int end = LONG.build(range.get(1)).intValue();
           result.add(new int[] { start, end });
@@ -252,7 +264,7 @@ public HotkeysInfo build(Object data) {
             case SELECTED_SLOTS:
               selectedSlots = parseSlotRanges(value);
               break;
-            case SAMPLED_COMMAND_SELECTED_SLOTS_US:
+            case SAMPLED_COMMANDS_SELECTED_SLOTS_US:
               sampledCommandSelectedSlotsUs = LONG.build(value);
               break;
             case ALL_COMMANDS_SELECTED_SLOTS_US:
@@ -308,7 +320,7 @@ public HotkeysInfo build(Object data) {
             case SELECTED_SLOTS:
               selectedSlots = parseSlotRanges(value);
               break;
-            case SAMPLED_COMMAND_SELECTED_SLOTS_US:
+            case SAMPLED_COMMANDS_SELECTED_SLOTS_US:
               sampledCommandSelectedSlotsUs = LONG.build(value);
               break;
             case ALL_COMMANDS_SELECTED_SLOTS_US:

diff --git a/src/test/java/redis/clients/jedis/commands/jedis/ClusterHotkeysCommandsTest.java b/src/test/java/redis/clients/jedis/commands/jedis/ClusterHotkeysCommandsTest.java
@@ -1,18 +1,39 @@
 package redis.clients.jedis.commands.jedis;
 
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hamcrest.Matchers.greaterThan;
+import static org.hamcrest.Matchers.greaterThanOrEqualTo;
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertNotNull;
 import static org.junit.jupiter.api.Assertions.assertThrows;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+import java.util.List;
+import java.util.Map;
 
 import io.redis.test.annotations.ConditionalOnEnv;
 import io.redis.test.annotations.EnabledOnCommand;
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.Tag;
 
+import redis.clients.jedis.HostAndPort;
+import redis.clients.jedis.RedisClient;
 import redis.clients.jedis.args.HotkeysMetric;
 import redis.clients.jedis.params.HotkeysParams;
+import redis.clients.jedis.resps.HotkeysInfo;
+import redis.clients.jedis.util.JedisClusterCRC16;
 import redis.clients.jedis.util.TestEnvUtil;
 
 /**
  * Tests that HOTKEYS commands are not supported in cluster mode.
+ * <p>
+ * The HOTKEYS command is a node-local operation that tracks hot keys on a single Redis instance. In
+ * a Redis Cluster, keys are distributed across multiple nodes, and there is no built-in mechanism
+ * to aggregate hotkeys data across all nodes. Therefore, HOTKEYS commands are intentionally
+ * disabled in cluster mode to avoid confusion and incorrect results.
+ * <p>
+ * Users who need hotkeys functionality in a cluster environment should connect directly to
+ * individual nodes and run HOTKEYS commands on each node separately.
  */
 @Tag("integration")
 @EnabledOnCommand("HOTKEYS")
@@ -39,4 +60,120 @@ public void hotkeysResetNotSupportedInCluster() {
   public void hotkeysGetNotSupportedInCluster() {
     assertThrows(UnsupportedOperationException.class, () -> cluster.hotkeysGet());
   }
+
+  // Test slots - consecutive slots (server groups them as a range) and a non-consecutive slot
+  private static final int SLOT_0 = 0;
+  private static final int SLOT_1 = 1;
+  private static final int SLOT_2 = 2;
+  private static final int SLOT_100 = 100; // Non-consecutive slot to test multiple ranges
+
+  // Keys with hash tags that hash to slots 0, 1, 2
+  // The hash tag content was found by iterating JedisClusterCRC16.getSlot()
+  private static final String KEY_SLOT_0 = "key{3560}"; // {3560} hashes to slot 0
+  private static final String KEY_SLOT_1 = "key{22179}"; // {22179} hashes to slot 1
+  private static final String KEY_SLOT_2 = "key{48756}"; // {48756} hashes to slot 2
+
+  /**
+   * Tests HOTKEYS with SLOTS parameter by connecting directly to a single cluster node using a
+   * standalone RedisClient. Verifies all response fields are correctly parsed.
+   */
+  @Test
+  public void hotkeysWithSlotsOnSingleClusterNode() {
+    // Verify our pre-computed keys hash to the expected slots
+    assertEquals(SLOT_0, JedisClusterCRC16.getSlot(KEY_SLOT_0));
+    assertEquals(SLOT_1, JedisClusterCRC16.getSlot(KEY_SLOT_1));
+    assertEquals(SLOT_2, JedisClusterCRC16.getSlot(KEY_SLOT_2));
+
+    HostAndPort nodeHostAndPort = endpoint.getHostsAndPorts().get(0);
+
+    try (RedisClient client = RedisClient.builder().hostAndPort(nodeHostAndPort)
+        .clientConfig(endpoint.getClientConfigBuilder().build()).build()) {
+
+      // Clean up any previous state
+      client.hotkeysStop();
+      client.hotkeysReset();
+
+      // Start hotkeys tracking with consecutive slots (0, 1, 2) and a non-consecutive slot (100)
+      // Server should group consecutive slots into a range and keep non-consecutive as single slot
+      String result = client
+          .hotkeysStart(HotkeysParams.hotkeysParams().metrics(HotkeysMetric.CPU, HotkeysMetric.NET)
+              .sample(2).slots(SLOT_0, SLOT_1, SLOT_2, SLOT_100));
+      assertEquals("OK", result);
+
+      // Generate traffic on keys that hash to slots 0, 1, 2
+      String[] keys = { KEY_SLOT_0, KEY_SLOT_1, KEY_SLOT_2 };
+      for (int i = 0; i < 50; i++) {
+        for (String key : keys) {
+          client.set(key, "value" + i);
+          client.get(key);
+        }
+      }
+
+      HotkeysInfo info = client.hotkeysGet();
+      assertNotNull(info);
+
+      // Verify tracking state
+      assertTrue(info.isTrackingActive());
+      assertEquals(2, info.getSampleRatio());
+
+      // Verify selected slots - should have 2 entries:
+      // 1. Range [0, 2] for consecutive slots 0, 1, 2
+      // 2. Single slot [100] for non-consecutive slot
+      List<int[]> selectedSlots = info.getSelectedSlots();
+      assertNotNull(selectedSlots);
+      assertEquals(2, selectedSlots.size());
+      // First entry: range [0, 2]
+      assertEquals(2, selectedSlots.get(0).length);
+      assertEquals(SLOT_0, selectedSlots.get(0)[0]);
+      assertEquals(SLOT_2, selectedSlots.get(0)[1]);
+      // Second entry: single slot [100]
+      assertEquals(1, selectedSlots.get(1).length);
+      assertEquals(SLOT_100, selectedSlots.get(1)[0]);
+
+      // Verify slot-specific CPU metrics (only present when SLOTS is used)
+      assertNotNull(info.getSampledCommandSelectedSlotsUs());
+      assertThat(info.getSampledCommandSelectedSlotsUs(), greaterThan(0L));
+      assertNotNull(info.getAllCommandsSelectedSlotsUs());
+      assertThat(info.getAllCommandsSelectedSlotsUs(), greaterThan(0L));
+      assertThat(info.getAllCommandsAllSlotsUs(), greaterThan(0L));
+
+      // Verify slot-specific network bytes metrics
+      assertNotNull(info.getNetBytesSampledCommandsSelectedSlots());
+      assertThat(info.getNetBytesSampledCommandsSelectedSlots(), greaterThan(0L));
+      assertNotNull(info.getNetBytesAllCommandsSelectedSlots());
+      assertThat(info.getNetBytesAllCommandsSelectedSlots(), greaterThan(0L));
+      assertThat(info.getNetBytesAllCommandsAllSlots(), greaterThan(0L));
+
+      // Verify timing fields
+      assertThat(info.getCollectionStartTimeUnixMs(), greaterThan(0L));
+      assertThat(info.getCollectionDurationMs(), greaterThanOrEqualTo(0L));
+      assertThat(info.getTotalCpuTimeUserMs(), greaterThanOrEqualTo(0L));
+      assertThat(info.getTotalCpuTimeSysMs(), greaterThanOrEqualTo(0L));
+      assertThat(info.getTotalNetBytes(), greaterThan(0L));
+
+      // Verify key metrics maps contain our 3 keys with values > 0
+      Map<String, Long> byCpuTimeUs = info.getByCpuTimeUs();
+      assertNotNull(byCpuTimeUs);
+      assertEquals(3, byCpuTimeUs.size());
+      assertTrue(byCpuTimeUs.containsKey(KEY_SLOT_0));
+      assertTrue(byCpuTimeUs.containsKey(KEY_SLOT_1));
+      assertTrue(byCpuTimeUs.containsKey(KEY_SLOT_2));
+      assertThat(byCpuTimeUs.get(KEY_SLOT_0), greaterThan(0L));
+      assertThat(byCpuTimeUs.get(KEY_SLOT_1), greaterThan(0L));
+      assertThat(byCpuTimeUs.get(KEY_SLOT_2), greaterThan(0L));
+
+      Map<String, Long> byNetBytes = info.getByNetBytes();
+      assertNotNull(byNetBytes);
+      assertEquals(3, byNetBytes.size());
+      assertTrue(byNetBytes.containsKey(KEY_SLOT_0));
+      assertTrue(byNetBytes.containsKey(KEY_SLOT_1));
+      assertTrue(byNetBytes.containsKey(KEY_SLOT_2));
+      assertThat(byNetBytes.get(KEY_SLOT_0), greaterThan(0L));
+      assertThat(byNetBytes.get(KEY_SLOT_1), greaterThan(0L));
+      assertThat(byNetBytes.get(KEY_SLOT_2), greaterThan(0L));
+
+      client.hotkeysStop();
+      client.hotkeysReset();
+    }
+  }
 }
diff --git a/src/test/resources/env/.env b/src/test/resources/env/.env
@@ -1,5 +1,5 @@
-REDIS_VERSION=8.4.0
-REDIS_STACK_VERSION=8.4.0
+REDIS_VERSION=8.6.0
+REDIS_STACK_VERSION=8.6.0
 CLIENT_LIBS_TEST_IMAGE=redislabs/client-libs-test
 REDIS_ENV_CONF_DIR=./
 REDIS_MODULES_DIR=/tmp

diff --git a/src/test/resources/env/.env.v8.6 b/src/test/resources/env/.env.v8.6
@@ -1,5 +1,5 @@
-REDIS_VERSION=custom-21651605017-debian-amd64
-REDIS_STACK_VERSION=custom-21651605017-debian-amd64
+REDIS_VERSION=8.6.0
+REDIS_STACK_VERSION=8.6.0
 CLIENT_LIBS_TEST_IMAGE=redislabs/client-libs-test
 REDIS_ENV_CONF_DIR=./
 REDIS_MODULES_DIR=/tmp