Massive memory leak in Blueprint Editor introduced with Unreal 4.9

System: 16GB ddr3 1866

Started the working project: 6GB/16GB RAM
After 15min: 12GB/16GB
After 30min: 15GB/16GB
After 1 hour: Program error: no such ram: exit


When getting near to 16GB needs to SAVE.
Close UE editor.
Open again the project (±6GB)