I recently acquired a Raspberry Pi 2 Model B to make a 24h torrent box. My external HDD is in ExFat (1TB USB3.0 - WD) and after installing the exfat drivers, I began to configure it for my purpose. The problem was after adding the second torrent, but also appears also in the several tries with only one torrent.
The problem is that when I start the torrent client (in my case QBittorrent) it starts to download with a speed of 3-5MB/s, but after several seconds (less than 1 minute) it begins to fall until it stops to download. Sometimes it crashes, other times I need to force close, and the only hint that I have, is that is related with the exfat.mount process. I observed it while it was downloading and the use of CPU is a little high (about 15-20%).
Can someone help with this? I tried also changing the distro from Raspbian to Ubuntu Mate and changing several parameters of the cache, but always I experienced the same problem.