Browse Prior Art Database

Performance Trace Facility

IP.com Disclosure Number: IPCOM000040484D
Original Publication Date: 1987-Nov-01
Included in the Prior Art Database: 2005-Feb-02
Document File: 2 page(s) / 51K

Publishing Venue

IBM

Related People

Knight, SA: AUTHOR [+3]

Abstract

A facility traces program flow and measures the pathlengths of multiple program modules executing in a computer system. The computer system has RAM and ROS storage. A program assist enables a logic analyzer to capture subprogram trace information in one measurement run. At the start and end of each program procedure, an instruction that writes a unique number (procedure ID) to a predefined fixed ROS address is inserted. Each program procedure is assigned a pair of these IDs. Fig. 1 shows an example of procedures writing to the ROS address. During execution, the single ROS location will be accessed by all the program procedures that execute. The write to the ROS location has no effect on the system other than surfacing to a data bus the procedure IDs for the logic analyzer to easily capture.

This text was extracted from a PDF file.
At least one non-text object (such as an image or picture) has been suppressed.
This is the abbreviated version, containing approximately 100% of the total text.

Page 1 of 2

Performance Trace Facility

A facility traces program flow and measures the pathlengths of multiple program modules executing in a computer system. The computer system has RAM and ROS storage. A program assist enables a logic analyzer to capture subprogram trace information in one measurement run. At the start and end of each program procedure, an instruction that writes a unique number (procedure ID) to a predefined fixed ROS address is inserted. Each program procedure is assigned a pair of these IDs. Fig. 1 shows an example of procedures writing to the ROS address. During execution, the single ROS location will be accessed by all the program procedures that execute. The write to the ROS location has no effect on the system other than surfacing to a data bus the procedure IDs for the logic analyzer to easily capture.

(Image Omitted)

A utility program takes the 'raw' logic analyzer trace data containing procedure IDs and converts the trace to one having the actual program procedure names along with the relative and absolute times. Fig. 2 shows an example of what trace/performance information could be gathered using this technique against the previous example. This technique easily allows pathlength measurement of a system using many program procedures as well as tracing the calling or nesting sequence of the procedures by the use of program assists combined with the use of a logic analyzer.

1

Page 2 of 2

2

[This page contains 4 pictures or other non-text objects]...