Remove unused cachingCost strategy runtime properties (#16918)

docs/configuration/index.md

@@ -887,8 +887,7 @@ These Coordinator static configurations can be defined in the `coordinator/runti
 |`druid.coordinator.kill.ignoreDurationToRetain`|A way to override `druid.coordinator.kill.durationToRetain` and tell the coordinator that you do not care about the end date of unused segment intervals when it comes to killing them. If true, the coordinator considers all unused segments as eligible to be killed.|false|
 |`druid.coordinator.kill.bufferPeriod`|The amount of time that a segment must be unused before it is able to be permanently removed from metadata and deep storage. This can serve as a buffer period to prevent data loss if data ends up being needed after being marked unused.|`P30D`|
 |`druid.coordinator.kill.maxSegments`|The number of unused segments to kill per kill task. This number must be greater than 0. This only applies when `druid.coordinator.kill.on=true`.|100|
-|`druid.coordinator.balancer.strategy`|Specify the type of balancing strategy for the Coordinator to use to distribute segments among the Historical services. `cachingCost` is logically equivalent to `cost` but is more CPU-efficient on large clusters. `diskNormalized` weights the costs according to the servers' disk usage ratios - there are known issues with this strategy distributing segments unevenly across the cluster. `random` distributes segments among services randomly.|`cost`|
-|`druid.coordinator.balancer.cachingCost.awaitInitialization`|Whether to wait for segment view initialization before creating the `cachingCost` balancing strategy. This property is enabled only when `druid.coordinator.balancer.strategy` is `cachingCost`. If set to true, the Coordinator will not start to assign segments, until the segment view is initialized. If set to false, the Coordinator will fallback to use the `cost` balancing strategy only if the segment view is not initialized yet. It may take much time to wait for the initialization since the `cachingCost` balancing strategy involves much computing to build itself.|false|
+|`druid.coordinator.balancer.strategy`|Specify the type of balancing strategy for the Coordinator to use to distribute segments among the Historical services. `diskNormalized` weights the costs according to the servers' disk usage ratios - there are known issues with this strategy distributing segments unevenly across the cluster. `random` distributes segments among services randomly.|`cost`|
 |`druid.coordinator.loadqueuepeon.http.repeatDelay`|The start and repeat delay (in milliseconds) for the load queue peon, which manages the load/drop queue of segments for any server.|1 minute|
 |`druid.coordinator.loadqueuepeon.http.batchSize`|Number of segment load/drop requests to batch in one HTTP request. Note that it must be smaller than `druid.segmentCache.numLoadingThreads` config on Historical service.|1|
 |`druid.coordinator.asOverlord.enabled`|Boolean value for whether this Coordinator service should act like an Overlord as well. This configuration allows users to simplify a Druid cluster by not having to deploy any standalone Overlord services. If set to true, then Overlord console is available at `http://coordinator-host:port/console.html` and be sure to set `druid.coordinator.asOverlord.overlordService` also.|false|

services/src/main/java/org/apache/druid/cli/CliCoordinator.java

@@ -101,7 +101,6 @@
 import org.apache.druid.server.coordinator.DruidCoordinator;
 import org.apache.druid.server.coordinator.MetadataManager;
 import org.apache.druid.server.coordinator.balancer.BalancerStrategyFactory;
-import org.apache.druid.server.coordinator.balancer.CachingCostBalancerStrategyConfig;
 import org.apache.druid.server.coordinator.compact.CompactionSegmentSearchPolicy;
 import org.apache.druid.server.coordinator.compact.NewestSegmentFirstPolicy;
 import org.apache.druid.server.coordinator.config.CoordinatorKillConfigs;
@@ -223,11 +222,6 @@ public void configure(Binder binder)
             JsonConfigProvider.bind(binder, "druid.coordinator.loadqueuepeon.http", HttpLoadQueuePeonConfig.class);
             JsonConfigProvider.bind(binder, "druid.coordinator.balancer", BalancerStrategyFactory.class);
             JsonConfigProvider.bind(binder, "druid.coordinator.segment", CoordinatorSegmentWatcherConfig.class);
-            JsonConfigProvider.bind(
-                binder,
-                "druid.coordinator.balancer.cachingCost",
-                CachingCostBalancerStrategyConfig.class
-            );
             JsonConfigProvider.bind(binder, "druid.coordinator.segmentMetadataCache", SegmentMetadataCacheConfig.class);
             binder.bind(DruidCoordinatorConfig.class);