The CPU seams to be the reason for slow <1 MByte/sec anonymous downloads.

possible problem
Running crypto on twisted thread blocks all other Tribler activity. Unclear if we needs 256bit GCM mode. Anything that checks a signature, decrypt a message, etc. needs to be traced.

possible long-term solution
Separate thread for the tunnel community or even an isolated thread for each community.
Low hanging fruit: parallel execution of relaying, make it multi-threaded. Real threads: Twisted reactor versus import multiprocessing...

goal

1. benchmark raw openssl C code GCM MBps.

2. Create a minimal benchmark comparing current situation in Tribler with alternatives. Not re-using Tribler code, but a performance test processing 10.000 UDP

• Only generating packets and decrypting one layer, then another layer. Current approach.
• Doing the same on a threadpool within Twisted.
• Separate Python OS process, communicate using a ringbuffer. Twisted has build-in support for this, treating it like just another thread.

EDIT: use 10k UDP packets through exit node as benchmark.