No it's not pure python. It's a combination. The underlying event loop uses libuv, a C library that's makes up the underlying core of nodejs. The marker of "Uvicorn" is an indicator of this as "Uvicorn" uses uvlib.
Overall the benchmark is testing a bit of both. The event loop runs on C but it has to execute a bit of python code when handling the request.
>If it's being done via a database on the local machine, and the communication with that database is not being done by something like Unix sockets, but by direct calls into a database library, then that's obviously going to cause latency problems because the worker can't yield during the database call.
I am almost positive it is being done with some form of non blocking sockets. The only other way to do this without sockets is to write to file and read from file.
There is no "direct library calls" as the database server exists as a separate process to the server process. Here's what occurs:
1. Server makes a socket connection to database.
2. Server sends a request to database
3. database receives request, reads from database file.
4. database sends information back to server.