diff --git a/dbms/include/DB/Interpreters/Aggregator.h b/dbms/include/DB/Interpreters/Aggregator.h
index 78651f88072..a79858db5bb 100644
--- a/dbms/include/DB/Interpreters/Aggregator.h
+++ b/dbms/include/DB/Interpreters/Aggregator.h
@@ -91,7 +91,7 @@ struct AggregationMethodKey64
 
 	/** Разместить дополнительные данные, если это необходимо, в случае, когда в хэш-таблицу был вставлен новый ключ.
 	  */
-	void onNewKey(iterator & it, size_t keys_size, size_t i, StringRefs & keys)
+	void onNewKey(iterator & it, size_t keys_size, size_t i, StringRefs & keys, Arena & pool)
 	{
 	}
 
@@ -114,7 +114,6 @@ struct AggregationMethodString
 	typedef Data::const_iterator const_iterator;
 
 	Data data;
-	Arena string_pool;		/// NOTE Может быть лучше вместо этого использовать aggregates_pool?
 
 	const ColumnString::Offsets_t * offsets;
 	const ColumnString::Chars_t * chars;
@@ -140,9 +139,9 @@ struct AggregationMethodString
 	static AggregateDataPtr & getAggregateData(Mapped & value) 				{ return value; }
 	static const AggregateDataPtr & getAggregateData(const Mapped & value) 	{ return value; }
 
-	void onNewKey(iterator & it, size_t keys_size, size_t i, StringRefs & keys)
+	void onNewKey(iterator & it, size_t keys_size, size_t i, StringRefs & keys, Arena & pool)
 	{
-		it->first.data = string_pool.insert(it->first.data, it->first.size);
+		it->first.data = pool.insert(it->first.data, it->first.size);
 	}
 
 	static void insertKeyIntoColumns(const_iterator & it, ColumnPlainPtrs & key_columns, size_t keys_size, const Sizes & key_sizes)
@@ -162,7 +161,6 @@ struct AggregationMethodFixedString
 	typedef Data::const_iterator const_iterator;
 
 	Data data;
-	Arena string_pool;		/// NOTE Может быть лучше вместо этого использовать aggregates_pool?
 
 	size_t n;
 	const ColumnFixedString::Chars_t * chars;
@@ -188,9 +186,9 @@ struct AggregationMethodFixedString
 	static AggregateDataPtr & getAggregateData(Mapped & value) 				{ return value; }
 	static const AggregateDataPtr & getAggregateData(const Mapped & value) 	{ return value; }
 
-	void onNewKey(iterator & it, size_t keys_size, size_t i, StringRefs & keys)
+	void onNewKey(iterator & it, size_t keys_size, size_t i, StringRefs & keys, Arena & pool)
 	{
-		it->first.data = string_pool.insert(it->first.data, it->first.size);
+		it->first.data = pool.insert(it->first.data, it->first.size);
 	}
 
 	static void insertKeyIntoColumns(const_iterator & it, ColumnPlainPtrs & key_columns, size_t keys_size, const Sizes & key_sizes)
@@ -228,7 +226,7 @@ struct AggregationMethodKeys128
 	static AggregateDataPtr & getAggregateData(Mapped & value) 				{ return value; }
 	static const AggregateDataPtr & getAggregateData(const Mapped & value) 	{ return value; }
 
-	void onNewKey(iterator & it, size_t keys_size, size_t i, StringRefs & keys)
+	void onNewKey(iterator & it, size_t keys_size, size_t i, StringRefs & keys, Arena & pool)
 	{
 	}
 
@@ -255,7 +253,6 @@ struct AggregationMethodHashed
 	typedef Data::const_iterator const_iterator;
 
 	Data data;
-	Arena keys_pool;		/// NOTE Может быть лучше вместо этого использовать aggregates_pool?
 
 	void init(ConstColumnPlainPtrs & key_columns)
 	{
@@ -274,9 +271,9 @@ struct AggregationMethodHashed
 	static AggregateDataPtr & getAggregateData(Mapped & value) 				{ return value.second; }
 	static const AggregateDataPtr & getAggregateData(const Mapped & value) 	{ return value.second; }
 
-	void onNewKey(iterator & it, size_t keys_size, size_t i, StringRefs & keys)
+	void onNewKey(iterator & it, size_t keys_size, size_t i, StringRefs & keys, Arena & pool)
 	{
-		it->second.first = placeKeysInPool(i, keys_size, keys, keys_pool);
+		it->second.first = placeKeysInPool(i, keys_size, keys, pool);
 	}
 
 	static void insertKeyIntoColumns(const_iterator & it, ColumnPlainPtrs & key_columns, size_t keys_size, const Sizes & key_sizes)
diff --git a/dbms/src/Interpreters/Aggregator.cpp b/dbms/src/Interpreters/Aggregator.cpp
index e68157fc365..a5579f97685 100644
--- a/dbms/src/Interpreters/Aggregator.cpp
+++ b/dbms/src/Interpreters/Aggregator.cpp
@@ -185,7 +185,7 @@ void Aggregator::executeImpl(
 		/// Если вставили новый ключ - инициализируем состояния агрегатных функций, и возможно, что-нибудь связанное с ключём.
 		if (inserted)
 		{
-			method.onNewKey(it, keys_size, i, keys);
+			method.onNewKey(it, keys_size, i, keys, *aggregates_pool);
 
 			AggregateDataPtr & aggregate_data = Method::getAggregateData(it->second);
 			aggregate_data = aggregates_pool->alloc(total_size_of_aggregate_states);
@@ -296,7 +296,7 @@ void Aggregator::mergeStreamsImpl(
 
 		if (inserted)
 		{
-			method.onNewKey(it, keys_size, i, keys);
+			method.onNewKey(it, keys_size, i, keys, *aggregates_pool);
 
 			AggregateDataPtr & aggregate_data = Method::getAggregateData(it->second);
 			aggregate_data = aggregates_pool->alloc(total_size_of_aggregate_states);
diff --git a/dbms/src/Interpreters/SplittingAggregator.cpp b/dbms/src/Interpreters/SplittingAggregator.cpp
index b9f8cc99138..f8f09e76236 100644
--- a/dbms/src/Interpreters/SplittingAggregator.cpp
+++ b/dbms/src/Interpreters/SplittingAggregator.cpp
@@ -312,7 +312,7 @@ void SplittingAggregator::aggregateThread(
 				
 				if (inserted)
 				{
-					it->first.data = result.key_string->string_pool.insert(ref.data, ref.size);
+					it->first.data = result.aggregates_pool->insert(ref.data, ref.size);
 					it->second = result.aggregates_pool->alloc(total_size_of_aggregate_states);
 
 					for (size_t j = 0; j < aggregates_size; ++j)
@@ -350,7 +350,7 @@ void SplittingAggregator::aggregateThread(
 
 				if (inserted)
 				{
-					it->first.data = result.key_fixed_string->string_pool.insert(ref.data, ref.size);
+					it->first.data = result.aggregates_pool->insert(ref.data, ref.size);
 					it->second = result.aggregates_pool->alloc(total_size_of_aggregate_states);
 
 					for (size_t j = 0; j < aggregates_size; ++j)
@@ -424,7 +424,7 @@ void SplittingAggregator::aggregateThread(
 
 				if (inserted)
 				{
-					it->second.first = extractKeysAndPlaceInPool(i, keys_size, key_columns, key, result.hashed->keys_pool);
+					it->second.first = extractKeysAndPlaceInPool(i, keys_size, key_columns, key, *result.aggregates_pool);
 					it->second.second = result.aggregates_pool->alloc(total_size_of_aggregate_states);
 
 					for (size_t j = 0; j < aggregates_size; ++j)