17.op/TEA.krueger.vahdat
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Application-Specific Virtual Memory Management 

Keith Krueger and Amin Vahdat

(Professor T. E. Anderson)

AT&T Bell Labs, Digital Equipment, MICRO, and (NSF) CDA-87-22788 (NYI)

Many scientific and database applications perform poorly when
they run on top of a traditional virtual memory implementation.
To help address this problem, several systems have been built
to allow an individual program the flexibility to use an
application-specific page replacement policy, in place of the
general-purpose policy provided by the operating system. This
has the potential to improve performance for the class of
applications limited by virtual memory behavior; however, to
realize this performance gain, application developers must
reimplement large parts of the virtual memory system, a
non-trivial programming task.

Our goal is to make it easy for programmers to develop new
application-specific page replacement policies. To do this, we
have developed an extensible object-oriented user-level
virtual memory system, and an interactive, graphical
performance monitor for virtual memory behavior. Together,
these help the user to identify problems with an application's
existing paging policy and to quickly develop and experiment
with alternative policies. We have used our tools to tune the
virtual memory performance of several applications, and are
currently experimenting with several memory-intensive
applications to determine the benefits and the limitations of
our tools.


[1]	K. Krueger, D. Loftesness, A. Vahdat, and T. E. Anderson, "Tools
for the Development of Application-Specific Virtual Memory
Management," Proc. Object-Oriented Programming Systems, Languages,
and Applications, September 1993.