1. A method for optimizing read operations from a storage device in a virtualized computing environment, the method comprising: monitoring read operations issued by an application running on a virtual machine's (VM) operating system, wherein the VM is hosted by a hypervisor providing access to a storage device in a virtualized computing environment; providing a first para-virtualized file system front end (PVFS FE) with direct access to a first cache, wherein the first cache is supported by the VM's operating system such that responsibility for servicing a read operation issued by the application running on the VM is managed by the VM's operating system, instead of the responsibility being passed to the hypervisor; and causing a virtual file system (VFS) supported by the VM's operating system to call on PVFS FE to service the read operation by attempting to read target data identified by the read request from the first cache supported by the VM's operating system, in response to determining that the read operation issued by the application is for reading the target data from the storage device, wherein if PVFS FE determines that the target data is available in the first cache, then PVFS FE satisfies the read operation by reading the target data from the first cache supported by the VM's operating system, instead of passing handling of the read request to the hypervisor, wherein if PVFS FE determines that the target data is not available in the first cache, then PVFS FE responds to the read operation by forwarding the read request for the target data to a second para-virtualized file system back end (PVFS BE) supported in the hypervisor, wherein the PVFS BE satisfies the read request forwarded by the PVFS FE by accessing the storage device, if the target data is not available in a second cache directly accessible to the PVFS BE.