diff --git a/fdbclient/ServerKnobs.cpp b/fdbclient/ServerKnobs.cpp
index 917664343c..fa105eb5e1 100644
--- a/fdbclient/ServerKnobs.cpp
+++ b/fdbclient/ServerKnobs.cpp
@@ -384,6 +384,7 @@ void ServerKnobs::initialize(Randomize randomize, ClientKnobs* clientKnobs, IsSi
 	init( ROCKSDB_CAN_COMMIT_DELAY_ON_OVERLOAD,                    1 );
 	init( ROCKSDB_CAN_COMMIT_DELAY_TIMES_ON_OVERLOAD,              5 );
 	init( ROCKSDB_COMPACTION_READAHEAD_SIZE,                   32768 ); // 32 KB, performs bigger reads when doing compaction.
+	init( ROCKSDB_BLOCK_SIZE,                                  32768 ); // 32 KB, size of the block in rocksdb cache.
 
 	// Leader election
 	bool longLeaderElection = randomize && BUGGIFY;
diff --git a/fdbclient/ServerKnobs.h b/fdbclient/ServerKnobs.h
index 13859ac9d6..d92d2c26df 100644
--- a/fdbclient/ServerKnobs.h
+++ b/fdbclient/ServerKnobs.h
@@ -316,6 +316,7 @@ public:
 	int ROCKSDB_CAN_COMMIT_DELAY_ON_OVERLOAD;
 	int ROCKSDB_CAN_COMMIT_DELAY_TIMES_ON_OVERLOAD;
 	int64_t ROCKSDB_COMPACTION_READAHEAD_SIZE;
+	int64_t ROCKSDB_BLOCK_SIZE;
 
 	// Leader election
 	int MAX_NOTIFICATIONS;
diff --git a/fdbserver/KeyValueStoreRocksDB.actor.cpp b/fdbserver/KeyValueStoreRocksDB.actor.cpp
index 38d5863eaa..17d94df11b 100644
--- a/fdbserver/KeyValueStoreRocksDB.actor.cpp
+++ b/fdbserver/KeyValueStoreRocksDB.actor.cpp
@@ -294,6 +294,9 @@ rocksdb::ColumnFamilyOptions getCFOptions() {
 		}
 		bbOpts.block_cache = rocksdb_block_cache;
 	}
+	if (SERVER_KNOBS->ROCKSDB_BLOCK_SIZE > 0) {
+		bbOpts.block_size = SERVER_KNOBS->ROCKSDB_BLOCK_SIZE;
+	}
 
 	options.table_factory.reset(rocksdb::NewBlockBasedTableFactory(bbOpts));