memray and later a custom request wrapper that output python gc statistics. Our main candidates for the leak are: grpc, asgi server itself, psycopg, django channels. All leaked to some degree. Alas, it did not became clear what caused the runaway leak at 30 MB/s. Capturing flamegraphs just before OOM kills would require some more engineering. Granian contained these situations until upgradings later that year made the system more stable to begin with.