Report Number: CSL-TR-94-656
Institution: Stanford University, Computer Systems Laboratory
Title: I/O Characterization and Attribute Cache Data for Eleven
Author: Richardson, Kathy J.
Date: December 1994
Abstract: Workloads generate a variety of disk I/O requests to access
file information, execute programs, and perform computation.
Workload characterization is crucial to optimizing I/O system
performance. This report contains detailed workload
characterization data for eleven measured workloads. It
includes numerous tables, and cache behavior plots for each
The workload I/O traces, from which the characterization is
derived, include both file system information and I/O system
information, where previous traces only included one or the
other. The additional information allows I/O characterization
at the system level, and greatly increases the body of
knowledge about the make-up and type of disk I/O requested.
The new information shows that the I/O request stream
contains statistically diverse components that can be
separated. This allows the important features of the workload
to be captured at the appropriate cache size, and increases
the total cache utilization.
Note: This technical report is a companion report to the
dissertation "I/O Characterization and Attribute Caches for
Improved I/O System Performance" (CSL-TR-94-655). While the
dissertation is self contained, this report is not; it
presents data that is analyzed and discussed only in the