Seeding thousands of torrents

Provided your client can handle those many torrents, I would not expect the CPU usage to differ by that much, because most of the work involved is disk and network I/O. Practically, you might face difficulties in maintaining so many (thousands) network connections to other clients.

If you can seed is as one torrent, then it's better to do just that than creating 2000 torrents.

With 2000 torrents, you will have a lot of overhead happening:

• Your processor needs to compute more, it needs to do the extra stuff 2000 times instead of once.
  It will also need to switch between threads a lot more, again causing overhead.

• Your memory will have a lot of overhead, all the overhead data for the file maps sums up a lot.

• Your disk I/O will have a lot of overhead, caching things in memory will be less effective.

• Your network I/O will have a lot of overhead, a lot more connections than needed are prepared.
  Your computer will probably not be able to handle all these extra connections,
  or you can set less connections which would make it be ineffective.

So, either make one torrent or split it up in some torrents, but don't create 2000 them...

Please don't forget that the user downloading your torrent can select what files he wants!
They will be happier with a small amount of torrents so that they have enough connections
so that the torrent downloads faster!

Oh, another hint: If your CPU and disk are fast enough you might want to compress things first... ;-)