[pfranz]

I was at a place that tried to distribute their files via bittorrent. I wasn't there for the initial implementation, but have dealt with it after it was used.

The data was immutable, so we didn't have that use-case. The tracker software we were using (one of the often used open source C++ ones) seemed to handle a couple hundred torrents just fine, but couldn't handle tens of thousands. Even if only a few were active. I'm not sure if it was excessive RAM or high CPU, but they built a wrapper tool to expire and re-add torrents as needed. I think technically it was limiting the number of seeds (from the central server) for different torrents.

There was also a lot of time/overhead in initiating a new download. This was exacerbated by the kludge mentioned above. Client would add the torrent, you would trigger a re-seed, then the client would wait awhile before checking again and finding the seed. Often this dance took much longer than the download itself.