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#Written by David Tam, 2000.           #
#davidkftam@netscape.net Copyright 2000#
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David Tam                                                  Tuesday, May 2, 2000.


                        Thesis Proposal
                        ===============
    
    My research interest is in the area of operating systems. Professor Michael
Stumm and his research group are currently collaborating with IBM to develop
the K42 operating system (OS). This research OS is being developed to address
performance and scalability issues of system software. I am interested in
investigating how K42 and its current hardware platform affect file system
design.
    
    Specifically, I intend to port the Hurricane File System (HFS) to K42 and
to study its performance. HFS was designed for a previous generation
shared-memory multiprocessor and OS, and consequently contains a valuable
framework to build upon. It was originally developed by Krieger [1,2] for the
Hurricane OS and Hector multiprocessor. My approach will be experimental in
nature, rather than theoretical. Through performance measurement and analysis,
I will optimize HFS for K42. Some important issues I will address are (1)
applicability of the HFS design, (2) workload selection, (3) component
redesign, and (4) HFS design assessment.
    
    Performance measurement and analysis will determine if HFS is making
efficient and intelligent use of the OS and hardware facilities. An important
issue I will address is in finding a suitable workload for evaluation. Possible
workloads include various macro benchmarks such as scientific and engineering
code, database management systems, transaction processing, client/server,
interactive, and streaming multimedia workloads.

    HFS will be tuned to retain its scalability and high I/O performance
properties. Tuning will require redesigning and/or re-implementing various
components of HFS. Perhaps modifications to the design of both HFS and K42 will
be necessary. K42 and its hardware platform provide various levels of
supporting infrastructure and services that may play a significant role in the
success of HFS. For instance, in the Hurricane OS and Hector multiprocessor,
the availability of an extremely efficient inter-process communication facility
(PPC: protected procedure call) plays a major role in minimizing overhead in
HFS. The optimization process will lead to an understanding of how K42 and its
hardware facilities affect the design, implementation, and performance of file
systems.  

    The optimization process will also verify the flexibility, scalability, and
robustness of HFS and K42. The current hardware facilities support larger scale
multiprocessors but exhibit larger disparities between CPU and memory speeds
than was available when HFS was initially conceived. Such a platform will
enable stress testing of both HFS and K42.

    To assess the design choices made in K42 and HFS, the overhead contributed
by the hardware, OS, and file system will be examined. For instance, K42
overhead may be due to OS resource contention among independent workloads that
are executing simultaneously. In such a situation, the design of K42 will be a
major determinant of performance and scalability of a file system. As a part of
the analysis, bounds on file system performance will be determined. Actual and
potential bottlenecks will be examined along with their dynamics. Understanding
the dynamics of bottlenecks may influence future design choices in the
operating system and file system.



REFERENCES
----------

[1]	O. Krieger, "HFS: A Flexible File System For Shared-Memory
    Multiprocessors," Ph.D. Thesis, Department of Electrical and Computer
    Engineering, University of Toronto, October 1994,
    ftp://ftp.cs.toronto.edu/pub/parallel/Okrieg_PhD.ps.Z.

[2]	O. Krieger and M. Stumm, "HFS: A Performance-Oriented Flexible File System
    Based on Building-Block Compositions," ACM Transactions on Computer
    Systems, Vol. 15, No. 3, August 1997, pp. 286-321,
    http://www.eecg.toronto.edu/~okrieg/papers/hfs_tocs.ps.gz.




Student,                        Supervisor,



______________________          ______________________


David Tam                       Michael Stumm