utorrent的磁碟快取
是把記憶體拿來做硬碟的快取以減少硬碟存取的次數
並不是把硬碟拿來當快取...
the disk cache is used to keep frequently accessed data in memory to reduce the number of reads and writes to the hard drive

只要下載和作種的資料夾不在c槽就ok了吧