quFiles: The Right File at the Right Time

A quFile is a unifying abstraction that simplifies data
management by encapsulating different physical representations
of the same logical data. Similar to a quBit
(quantum bit), the particular representation of the logical
data displayed by a quFile is not determined until the
moment it is needed. The representation returned by a
quFile is specified by a data-specific policy that can take
into account context such as the application requesting
the data, the device on which data is accessed, screen
size, and battery status. We demonstrate the generality
of the quFile abstraction by using it to implement
six case studies: resource management, copy-on-write
versioning, data redaction, resource-aware directories,
application-aware adaptation, and platform-specific encoding.
Most quFile policies were expressed using less
than one hundred lines of code. Our experimental results
show that, with caching and other performance optimizations,
quFiles add less than 1%