I had a GCP Cloud Run function that rendered videos. It was fine for one video per request but after that it slowed to a crawl and needed to shut down to clear out whatever was wrong. I assume a memory leak in MoviePy? Spent a couple of days looking at multiple options and trying different things, in the end I just duplicated the service so I had three of them and rotated which one we sent video renders to and do each render one at a time. It was by far the cheapest solution, means we processed them in parallel rather than serially so it was faster, all in all it worked a treat.