Abstract: Various methods and systems for optimizing cache consistency are disclosed. For example, one method involves writing data to a file during a write transaction. The file is stored in a persistent storage device and cached in a non-volatile storage device. The method determines if an in-memory flag associated with the persistent storage device set. If the in-memory flag is not set, the method increases a generation count associated with the persistent storage device before a write transaction is performed on the file. The method then sets the in-memory flag before performing the write transaction on the file. In other examples, the method involves using a persistent flag associated with the non-volatile storage device to maintain cache consistency during a data freeze related to the taking of a snapshot by synchronizing generation counts associated with the persistent storage device and the non-volatile storage device.

Abstract: Various systems and methods for inhibiting a modified block of data from being written to an underlying persistent storage device are disclosed. A cache is maintained by a file system and the cache is implemented to temporarily cache portions of application data for an application. The application data for the application is stored on the underlying persistent storage device. Metadata is accessed if it is detected that a block of data in the cache has been modified. The metadata indicates that the block of data is not needed for the integrity of the application. In response to the metadata, the modified block of data is inhibited from being written to the underlying persistent storage device.

Abstract: A client without direct access to a server performs commands on files of the server's file system, wherein the file system is made available by a network file system protocol. Calls to access the file system on the server are filtered. A call is identified that is passed a parameter comprising a filename with an identifiable filename extension. The identifiable filename extension is interpreted as indicating that the identified call was made as part of an attempt to execute an operation that is overloaded with a different command. It is determined, from the identifiable filename extension, which command is to be executed instead of the operation. Once the command to be executed is determined, the filename extension is removed from the parameter, and the determined command is executed instead of the overloaded operation.