Browse Prior Art Database

Performance Data Reduction

IP.com Disclosure Number: IPCOM000105606D
Original Publication Date: 1993-Aug-01
Included in the Prior Art Database: 2005-Mar-20
Document File: 2 page(s) / 33K

Publishing Venue

IBM

Related People

Acosta, V: AUTHOR [+2]

Abstract

Described is a method for deriving meaningful performance information from low-level computer performance measurements.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 86% of the total text.

Performance Data Reduction

      Described is a method for deriving meaningful performance
information from low-level computer performance measurements.

      The performance data generated from a computer operating system
such as OS/2* 2.0 is quite low-level, and not meaningful for
performance analysis.  Performance data is obtained from a computer
system by taking a snapshot of counter values and timer values at
periodic intervals.  This low-level data, called Level 1 (L1) data,
is specific to the hardware and software under test.

      A set of pre-defined formulas is used to derive performance
information from the low-level data that is meaninful and familiar to
the analyst.  The formulas calculate higher-level information, called
Level 2 (L2) information, using the L1 data for each snapshot.  L2
values may be calculated dynamically (i.e.  immediately for each
snapshot), or at post-processing time.  The characteristics of the L2
values are:

o   Their units are one of the following:
    -   Utilization, or percent capacity
    -   Time per Event, or response time
    -   Rate, or frequency of occurence, or throughput
    -   Ratio, of one of the above to another.
o   They combine only L1 values that are guaranteed to be consistent
    with respect to the time their values were read.

Examples of L2 values are:

      Disk Utilization  = (DiskReadTime + DiskWriteTime +
DiskSeekTime) /
TotalTime

      Disk Read Time ...