HistorySpy CEDAR 10.1 FOR INTERNAL XEROX USE ONLY HistorySpy A threads-oriented stack-tracing performance tool for Cedar Michael Plass c Copyright 1990, 1991 Xerox Corporation. All rights reserved. Abstract: This is the data-collection part of the Cedar History Spy. See ThreadsVis for the data analysis. History Spy collects information about the forking, waiting and execution of threads at millisecond granularity. ThreadsVis displays this information, thread by thread, showing the synchronization interaction between threads. Created by: Carl Hauser, with thanks to Michael Plass's Spy Maintained by: Carl Hauser:PARC:Xerox Keywords: performance measurement, tuning, timing, CPU usage XEROX Xerox Corporation Palo Alto Research Center 3333 Coyote Hill Road Palo Alto, California 94304 For Internal Xerox Use Only News December 8, 1992 First release to Cedar10.1 Introduction HistorySpy where (the stack) and when threads sleep and wake up. It collects a lot of data in a short time so it works best if you start it and then stop it no more than a few seconds later. This is unlike the Spy which gives the best picture if it aggregates data over a fairly long period of time. The HistorySpy implementation is based on that of Spy, with help from PCR. Commands These commands may be used to start and stop the Spy from a Commander. HistorySpyStart Start the spy. Arguments: -n => preallocate n spy tree nodes (default 10000). HistorySpyHalt Stop the spy. HistorySpyWrite Write the results of the last spy session to specified file (or to standard out, if no argument is provided). HistorySpyStop Same as HistorySpyHalt; HistorySpyWrite. Since writing uses the PCR load state, when spying on loading it is best to use HistorySpyHalt and then use HistorySpyWrite later when the loading is finished: otherwise, writing will be unable to look up some pc values and will yield empty strings instead of procedure names in the data. Client program interface HistorySpy.mesa provides a client interface to the history spy, in case somebody wants a different UI. See Also ThreadsVis.tioga tells you how to use a gargoyle-based tool for interpreting the results. SpyDoc describes the Spy: a tool for looking at aggregated information rather than event-by-event information. D HistorySpyDoc.tioga Chauser, December 8, 1992 3:41 pm PST ONewlineDelimiter (cedardoc) styleMark LastEditedJ%J LastEditedJ LastEditedIunleaded centerHeaders K centerFooter y)Ititle Isubtitle;Iauthors Iabstractms>?O b b YfO  ;O%O 3