diff --git a/fdbclient/ServerKnobs.cpp b/fdbclient/ServerKnobs.cpp
index 115a588763..9e1f86907b 100644
--- a/fdbclient/ServerKnobs.cpp
+++ b/fdbclient/ServerKnobs.cpp
@@ -143,6 +143,7 @@ void ServerKnobs::initialize(Randomize randomize, ClientKnobs* clientKnobs, IsSi
 	init( WIGGLING_RELOCATION_PARALLELISM_PER_SOURCE_SERVER,       2 ); if( randomize && BUGGIFY ) WIGGLING_RELOCATION_PARALLELISM_PER_SOURCE_SERVER = 1;
 	init( RELOCATION_PARALLELISM_PER_SOURCE_SERVER,                2 ); if( randomize && BUGGIFY ) RELOCATION_PARALLELISM_PER_SOURCE_SERVER = 1;
 	init( RELOCATION_PARALLELISM_PER_DEST_SERVER,                 10 ); if( randomize && BUGGIFY ) RELOCATION_PARALLELISM_PER_DEST_SERVER = 1; // Note: if this is smaller than FETCH_KEYS_PARALLELISM, this will artificially reduce performance. The current default of 10 is probably too high but is set conservatively for now.
+	init( MERGE_RELOCATION_PARALLELISM_PER_TEAM,                   6 ); if (randomize && BUGGIFY ) MERGE_RELOCATION_PARALLELISM_PER_TEAM = 1;
 	init( DD_QUEUE_MAX_KEY_SERVERS,                              100 ); // Do not buggify
 	init( DD_REBALANCE_PARALLELISM,                               50 );
 	init( DD_REBALANCE_RESET_AMOUNT,                              30 );
diff --git a/fdbclient/include/fdbclient/ServerKnobs.h b/fdbclient/include/fdbclient/ServerKnobs.h
index c1c9ef8c9b..0e75161652 100644
--- a/fdbclient/include/fdbclient/ServerKnobs.h
+++ b/fdbclient/include/fdbclient/ServerKnobs.h
@@ -132,6 +132,7 @@ public:
 	                                                          // than healthy priority
 	double RELOCATION_PARALLELISM_PER_SOURCE_SERVER;
 	double RELOCATION_PARALLELISM_PER_DEST_SERVER;
+	double MERGE_RELOCATION_PARALLELISM_PER_TEAM;
 	int DD_QUEUE_MAX_KEY_SERVERS;
 	int DD_REBALANCE_PARALLELISM;
 	int DD_REBALANCE_RESET_AMOUNT;
diff --git a/fdbserver/DDRelocationQueue.actor.cpp b/fdbserver/DDRelocationQueue.actor.cpp
index d5ede05fae..df81b8052a 100644
--- a/fdbserver/DDRelocationQueue.actor.cpp
+++ b/fdbserver/DDRelocationQueue.actor.cpp
@@ -433,8 +433,13 @@ int getSrcWorkFactor(RelocateData const& relocation, int singleRegionTeamSize) {
 		// we want to set PRIORITY_PERPETUAL_STORAGE_WIGGLE to a reasonably large value
 		// to make this parallelism take effect
 		return WORK_FULL_UTILIZATION / SERVER_KNOBS->WIGGLING_RELOCATION_PARALLELISM_PER_SOURCE_SERVER;
-	else // for now we assume that any message at a lower priority can best be assumed to have a full team left for work
+	else if (relocation.priority == SERVER_KNOBS->PRIORITY_MERGE_SHARD)
+		return WORK_FULL_UTILIZATION / SERVER_KNOBS->MERGE_RELOCATION_PARALLELISM_PER_TEAM;
+	else { // for now we assume that any message at a lower priority can best be assumed to have a full team left for
+		   // work
+
 		return WORK_FULL_UTILIZATION / singleRegionTeamSize / SERVER_KNOBS->RELOCATION_PARALLELISM_PER_SOURCE_SERVER;
+	}
 }
 
 int getDestWorkFactor() {
diff --git a/fdbserver/DDShardTracker.actor.cpp b/fdbserver/DDShardTracker.actor.cpp
index 1e0d0e91e2..3bb481a84d 100644
--- a/fdbserver/DDShardTracker.actor.cpp
+++ b/fdbserver/DDShardTracker.actor.cpp
@@ -127,6 +127,12 @@ int64_t getMaxShardSize(double dbSizeEstimate) {
 		size = std::max(size, static_cast<int64_t>(SERVER_KNOBS->MAX_LARGE_SHARD_BYTES));
 	}
 
+	TraceEvent("MaxShardSize")
+	    .suppressFor(60.0)
+	    .detail("Bytes", size)
+	    .detail("EstimatedDbSize", dbSizeEstimate)
+	    .detail("SqrtBytes", SERVER_KNOBS->SHARD_BYTES_PER_SQRT_BYTES)
+	    .detail("AllowLargeShard", SERVER_KNOBS->ALLOW_LARGE_SHARD);
 	return size;
 }
 
@@ -933,9 +939,6 @@ Future<Void> shardMerger(DataDistributionTracker* self,
 	const UID actionId = deterministicRandom()->randomUniqueID();
 	const Severity stSev = static_cast<Severity>(SERVER_KNOBS->DD_SHARD_TRACKING_LOG_SEVERITY);
 	int64_t maxShardSize = self->maxShardSize->get().get();
-	if (SERVER_KNOBS->ALLOW_LARGE_SHARD) {
-		maxShardSize = SERVER_KNOBS->MAX_LARGE_SHARD_BYTES;
-	}
 
 	auto prevIter = self->shards->rangeContaining(keys.begin);
 	auto nextIter = self->shards->rangeContaining(keys.begin);
@@ -1125,10 +1128,6 @@ ACTOR Future<Void> shardEvaluator(DataDistributionTracker* self,
 	StorageMetrics const& stats = shardSize->get().get().metrics;
 	auto bandwidthStatus = getBandwidthStatus(stats);
 
-	if (SERVER_KNOBS->ALLOW_LARGE_SHARD) {
-		shardBounds.max.bytes = SERVER_KNOBS->MAX_LARGE_SHARD_BYTES;
-	}
-
 	bool sizeSplit = stats.bytes > shardBounds.max.bytes,
 	     writeSplit = bandwidthStatus == BandwidthStatusHigh && keys.begin < keyServersKeys.begin;
 	bool shouldSplit = sizeSplit || writeSplit;