Thursday, April 7, 2005
12:00 pm - 1:00 pm
Wean Hall, Room 8220
Carnegie Mellon University
Comparison Based File Server Verification
Debugging servers is tough. When it comes to servers, "correct"
behavior is difficult to define. The published specification may describe
expected behavior in a vague manner, or not at all. Even worse, an implementation
might have become so popular that it has introduced a de facto standard
that does not conform to the original specification.
We propose a testing method which compares, for approximately the same
client request, the response from a known working implementation called
the reference server and the responses from a system under test (SUT)
called the developmental server. Not only does this method allow for detecting
differences between the servers' responses, it also allows for live client
testing and performance comparisons.
Our prototype, called the Tee, implements comparison based file server
verification for the NFS version 3 protocol. This talk will cover the
design of our NFS Tee, the synchronization of objects between the two
servers, and the results that we have gotten.
This talk is based on joint work with Yuen-Lin Tan at VMWare, John Strunk,
and Greg Ganger.
Terrence is a systems programmer at Carnegie Mellon University. He works
in the Parallel Data Laboratory under the supervision of Greg Ganger and
is interested in storage systems and NFS. Terrence received his BS in
Computer Science from Carnegie Mellon University in 2004 and plans to
pursue a graduate degree in the near future.
Seminar Info Contact:
or visit http://www.pdl.cmu.edu/SDI/