DATE: Thursday, February 19, 2004
TIME: Noon - 1 pm
PLACE: Wean Hall 8220

John Linwood Griffin

Making Better Use of Storage in Computer Systems
(via explicit information sharing across the storage interface)

The interface between operating systems and peripheral components (such as locally-attached storage devices) is often a demarcation point in computer systems: system designers typically provide for isolated computational hardware and data management on each side of the interface. My research argues the advantages of explicit information sharing across this narrow junction: packaging and exporting select characteristics from each side--in effect, sharing additional information across the existing communication paths--provides opportunities to enhance data management, peripheral efficiency, and overall system functionality. In this way, the complete system becomes greater than the sum of its parts.

In this talk I describe two of my recent projects toward this ideal: track-aligned extents and storage-based intrusion detection systems (IDSes). (1) Track-alinged extents allow OSes to match disk access patterns to the characteristics of modern disk drives. By allocating and accessing related data on disk track boundaries, a system can avoid most rotational latency and track crossing overheads--which can account for a substantial fraction of a request's service time. (2) Storage-based IDSes provide a unique vantage point for auditing storage accesses: a storage device sees all changes to persistently stored data, allowing it to watch for data modifications characteristic of system intrusions and to issue alerts to an administrator about the corresponding client systems.

Doctoral candidate John Linwood Griffin is a student of Greg Ganger with the Parallel Data Laboratory at Carnegie Mellon. By day he has broad interests in engineering and technology, including his current research involving the interaction of computer systems with disk drives and novel storage devices. By night he prowls the streets of steeltown, singing baritone with the Mendelssohn Choir of Pittsburgh and the Pittsburgh Symphony, deftly cooking up quality gourmet meals for his quality friends, and reminiscing about having grown up in the Deep South in the wayward days of yesteryear. Mr. Griffin holds computer engineering degrees from Auburn (B.C.E., 1998) and Carnegie Mellon (M.S., 2000). He is a recipient of the NSF Graduate Fellowship Award and the Intel Foundation Ph.D. Fellowship Award.

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