New Transmission add-on thread

I've been trying around a bit and the memory usage has me completely stunned... So far I've noticed that the used amount of memory depends on the setting for cache-size-mb, however, I don't see the relation.
I tried to get an idea by connecting to only a few peers with 2 torrents and changing the cache settings. The torrents each had 200+ seeds and I waited about 5 minutes after starting Transmission. These were the results:
cache-size-mb -> mem used @ peers connected -> avg download speed
2MB -> 10MB @ 14 peers -> ~150kB/s
4MB -> 15MB @ 30 peers -> ~300kB/s
8MB -> 21MB @ 23 peers -> ~400kB/s
16MB -> 33MB @ 15 peers -> ~400kB/s
32MB -> 58MB @ 21 peers -> ~200kB/s
64MB -> 78MB @ 23 peers -> ~150kB/s
128MB -> 44MB @ 25 peers -> ~100kB/s
256MB -> 59MB @ 23 peers -> ~130kB/s

So this obviously wasn't leading to anything useful. Maybe if I would let the torrents download for a few hours that it would stabalize to something useful, but I didn't have the time for that.

After that I tried one torrent (deleting the others) which had about 100 seeds of which I knew that it was very fast. The total size was 175MB. cache-size-mb was 256MB
Downloading at avg 2.5MB/s from 22 peers, Transmission's memory usage peaked at 536MB...
At cache-size-mb of 2MB, that same torrent reached the same maximum speed (~3MB/s) at 24 peers, but the used memory didn't get above 12MB. The download speed did vary a lot though and the average went down to about 1.7MB/s.

Conclusion:
- I've got no idea how it works

Untill someone tells me otherwise, I'll just put the setting back to 256MB. The low free memory doesn't cause any problems as far as I've noticed so I'll just don't look at it ;)