Skip unnecessary string format in RemoteStoreMigrationAllocationDecid…

…er when not in debug mode (#16299) (#16301)

(cherry picked from commit 5d2d392)

Signed-off-by: Rishab Nahata <[email protected]>
Signed-off-by: github-actions[bot] <github-actions[bot]@users.noreply.github.com>
Co-authored-by: github-actions[bot] <github-actions[bot]@users.noreply.github.com>

server/src/main/java/org/opensearch/cluster/routing/allocation/decider/RemoteStoreMigrationAllocationDecider.java

@@ -89,7 +89,7 @@ public Decision canAllocate(ShardRouting shardRouting, RoutingNode node, Routing
  return allocation.decision(
  Decision.YES,
  NAME,
- getDecisionDetails(true, shardRouting, targetNode, " for strict compatibility mode")
+ getDecisionDetails(true, shardRouting, targetNode, " for strict compatibility mode", allocation)
  );
  }
 
@@ -103,19 +103,23 @@ public Decision canAllocate(ShardRouting shardRouting, RoutingNode node, Routing
  return allocation.decision(
  isNoDecision ? Decision.NO : Decision.YES,
  NAME,
- getDecisionDetails(!isNoDecision, shardRouting, targetNode, reason)
+ getDecisionDetails(!isNoDecision, shardRouting, targetNode, reason, allocation)
  );
  } else if (migrationDirection.equals(Direction.DOCREP)) {
  // docrep migration direction is currently not supported
- return allocation.decision(Decision.YES, NAME, getDecisionDetails(true, shardRouting, targetNode, " for DOCREP direction"));
+ return allocation.decision(
+ Decision.YES,
+ NAME,
+ getDecisionDetails(true, shardRouting, targetNode, " for DOCREP direction", allocation)
+ );
  } else {
  // check for remote store backed indices
  if (remoteSettingsBackedIndex && targetNode.isRemoteStoreNode() == false) {
  // allocations and relocations must be to a remote node
  String reason = new StringBuilder(" because a remote store backed index's shard copy can only be ").append(
  (shardRouting.assignedToNode() == false) ? "allocated" : "relocated"
  ).append(" to a remote node").toString();
- return allocation.decision(Decision.NO, NAME, getDecisionDetails(false, shardRouting, targetNode, reason));
+ return allocation.decision(Decision.NO, NAME, getDecisionDetails(false, shardRouting, targetNode, reason, allocation));
  }
 
  if (shardRouting.primary()) {
@@ -128,9 +132,9 @@ public Decision canAllocate(ShardRouting shardRouting, RoutingNode node, Routing
  // handle scenarios for allocation of a new shard's primary copy
  private Decision primaryShardDecision(ShardRouting primaryShardRouting, DiscoveryNode targetNode, RoutingAllocation allocation) {
  if (targetNode.isRemoteStoreNode() == false) {
- return allocation.decision(Decision.NO, NAME, getDecisionDetails(false, primaryShardRouting, targetNode, ""));
+ return allocation.decision(Decision.NO, NAME, getDecisionDetails(false, primaryShardRouting, targetNode, "", allocation));
  }
- return allocation.decision(Decision.YES, NAME, getDecisionDetails(true, primaryShardRouting, targetNode, ""));
+ return allocation.decision(Decision.YES, NAME, getDecisionDetails(true, primaryShardRouting, targetNode, "", allocation));
  }
 
  // Checks if primary shard is on a remote node.
@@ -150,20 +154,41 @@ private Decision replicaShardDecision(ShardRouting replicaShardRouting, Discover
  return allocation.decision(
  Decision.NO,
  NAME,
- getDecisionDetails(false, replicaShardRouting, targetNode, " since primary shard copy is not yet migrated to remote")
+ getDecisionDetails(
+ false,
+ replicaShardRouting,
+ targetNode,
+ " since primary shard copy is not yet migrated to remote",
+ allocation
+ )
  );
  }
  return allocation.decision(
  Decision.YES,
  NAME,
- getDecisionDetails(true, replicaShardRouting, targetNode, " since primary shard copy has been migrated to remote")
+ getDecisionDetails(
+ true,
+ replicaShardRouting,
+ targetNode,
+ " since primary shard copy has been migrated to remote",
+ allocation
+ )
  );
  }
- return allocation.decision(Decision.YES, NAME, getDecisionDetails(true, replicaShardRouting, targetNode, ""));
+ return allocation.decision(Decision.YES, NAME, getDecisionDetails(true, replicaShardRouting, targetNode, "", allocation));
  }
 
  // get detailed reason for the decision
- private String getDecisionDetails(boolean isYes, ShardRouting shardRouting, DiscoveryNode targetNode, String reason) {
+ private String getDecisionDetails(
+ boolean isYes,
+ ShardRouting shardRouting,
+ DiscoveryNode targetNode,
+ String reason,
+ RoutingAllocation allocation
+ ) {
+ if (allocation.debugDecision() == false) {
+ return null;
+ }
  return new StringBuilder("[").append(migrationDirection.direction)
  .append(" migration_direction]: ")
  .append(shardRouting.primary() ? "primary" : "replica")