possessed by portable devices, while simultaneously preserving the consistency, robustness and ease of shar- ing/collaboration provided by distributed file systems.
One can envision many extensions to lookaside caching. For example, the client cache manager could track portable device state and update stale files auto- matically. This would require a binding between the name space on the device and the name space of the dis- tributed file system. With this change, a portable device effectively becomes an extension of the client’s cache. Another extension would be to support lookaside on in- dividual blocks of a file rather than a
Overall, we believe that the current design of looka- side caching represents a sweet spot in the space of de- sign tradeoffs. It is conceptually simple, easy to im- plement, and tolerant of human error. It provides good performance and availability benefits without compro- mising the strengths of portable storage devices or dis- tributed file systems. A user no longer has to choose be- tween distributed and portable storage. You can cache as well as carry!
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