temporary enable for testing

src/Core/Settings.h

@@ -139,7 +139,7 @@ static constexpr UInt64 operator""_GiB(unsigned long long value)
     M(UInt64, group_by_two_level_threshold_bytes, 50000000, "From what size of the aggregation state in bytes, a two-level aggregation begins to be used. 0 - the threshold is not set. Two-level aggregation is used when at least one of the thresholds is triggered.", 0) \
     M(Bool, distributed_aggregation_memory_efficient, true, "Is the memory-saving mode of distributed aggregation enabled.", 0) \
     M(UInt64, aggregation_memory_efficient_merge_threads, 0, "Number of threads to use for merge intermediate aggregation results in memory efficient mode. When bigger, then more memory is consumed. 0 means - same as 'max_threads'.", 0) \
-    M(Bool, enable_memory_bound_merging_of_aggregation_results, false, "Enable memory bound merging strategy for aggregation. Set it to true only if all nodes of your clusters have versions >= 22.10.", 0) \
+    M(Bool, enable_memory_bound_merging_of_aggregation_results, true, "Enable memory bound merging strategy for aggregation. Set it to true only if all nodes of your clusters have versions >= 22.10.", 0) \
     M(Bool, enable_positional_arguments, true, "Enable positional arguments in ORDER BY, GROUP BY and LIMIT BY", 0) \
     M(Bool, enable_extended_results_for_datetime_functions, false, "Enable date functions like toLastDayOfMonth return Date32 results (instead of Date results) for Date32/DateTime64 arguments.", 0) \
     \

tests/performance/memory_bound_merging.xml

@@ -1,6 +1,5 @@
 <test>
   <settings>
-    <enable_memory_bound_merging_of_aggregation_results>1</enable_memory_bound_merging_of_aggregation_results>
     <optimize_aggregation_in_order>1</optimize_aggregation_in_order>
   </settings>
 

tests/queries/0_stateless/02343_aggregation_pipeline.reference

@@ -74,10 +74,10 @@ ExpressionTransform × 16
   (MergingAggregated)
   Resize 1 → 16
     MergingAggregatedTransform
-      Resize 18 → 1
+      Resize 3 → 1
         (Union)
           (Aggregating)
-          Resize 16 → 16
+          Resize 16 → 1
             AggregatingTransform × 16
               (Expression)
               ExpressionTransform × 16