Read cache inefficient?

[chupakabra]

When read cache is enabled uTorrent reads from file twice more data then that was seeded. When read cache is disabled file read data amount is slightly lower than seeded data amount. See example:

Uploaded: 279.9 MB

Read from file: 575 MB

[Firon]

The point of the read cache is largely to reduce the NUMBER of reads/writes for performance's sake. It may have read more data, but it had 1/3 the number of reads from file compared to cache, which means the cache did its job. Hard drives are really bad at lots of small, random i/o.