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Characterizing and Back-Porting Performance Improvement



Clif Flynt, Phil Brooks, Donald G. Porter


The Tcl interpreter is constantly being modified and improved. Improvements include new features and performance boosts. Everyone wants to use the latest releases with the newest improvements, but corporate users with large code bases may not be able to do this. Reworking an extremely large code base can take longer than the interval between Tcl releases. These users may need a change to be back-ported to the version of Tcl that they are using. A Tcl release includes many changes and identifying the modification that caused a particular performance boost isn't always simple, particularly if the performance boost of interest was a side-effect of other improvements. This paper describes the discovery of a thread-performance issue in Tcl 8.4 which was fixed in 8.5, a semi-automated technique for tracking down the code modification that improved the performance, and a discussion back-porting the improvement.
Proceedings Title
20'th Annual Tcl/Tk Conference
Conference Dates
September 25-27, 2013
Conference Location
New Orleans, LA, US


Flynt, C. , Brooks, P. and Porter, D. (2013), Characterizing and Back-Porting Performance Improvement, 20'th Annual Tcl/Tk Conference, New Orleans, LA, US, [online], (Accessed June 18, 2024)


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Created September 24, 2013, Updated October 12, 2021