1. A computer-implemented method for reducing the latency of an anticipated read of disk blocks from a swap file in a virtualized environment, the environment including: a host swap file maintained by a host operating system and a virtual machine (VM) that includes a guest swap file maintained by a guest operating system, the method comprising: identifying, in the guest swap file, a sequence of disk blocks that was written by the guest operating system; detecting, within the sequence of disk blocks, a first disk block that contains a reference to a second disk block that is stored in the host swap file; and replacing the first disk block in the guest swap file with the second disk block.