presto memory usage mechanism problem, after the execution of the calculation task, the memory usage is not reduced

[mengbaba3316]

Hi, I am new to presto and I am having memory-related problems with presto and would like to ask for help. I configured presto with 8GB of jvm memory, every time I performed a query calculation, presto's memory usage gradually increased until I reached 8GB, but when some query calculations were finished, presto's memory usage did not decrease, I do not know why, here are my several guesses

1. presto increases memory to the maximum limit of the jvm based on the number of tasks, then cleans up memory when it is full and new query computing tasks come in
2. presto increases memory to the maximum limit of the jvm based on the number of tasks, then cleans up memory when it is full and new query computing tasks come in I hope you can help me, thank you very much