I just finished implementing mainline dht with a flat based routing table. I recall from kademilia something about an updated peer list and efficient key republishing and I started to wonder if after a certain amount of time I should remove peers from peer lists. But I can't find anything in bep about it.
I'm asking about BitTorrent peers.
Yes, they should only be stored for a finite amount of time. The spec seems to be silent on that. Libtorrent uses 45min timeout.
Qbittorrent seems to only send out 20 peers at most while my implementation has up to 300
It's probably only returning a sample of what it stores to keep UDP packet sizes below the link MTU.