[ptp-dev] The State of the TAU Plugins

[wspear <wspear@xxxxxxxxxxxxxx>]

Greetings,
Here is a quick overview of the TAU plugins as they stand now and their impending improvement.

As demonstrated at Supercomputing, the plugins have been almost totally overhauled from the previously committed versions.  Instrumentation options have been moved from a workspace-wide options panel to a run-configuration specific performance analysis tab.  Profile data is now collected in and displayable from a database navigable within Eclipse.  TAU's selective instrumentation capabilities were given an interface within the Eclipse workspace.

Since Supercomputing there have been several bugfixes and architectural changes.  The TAU plugin's Launch Configuration Delegate now essentially wraps the PTP's.  

Presently the scheme for performance analysis launching is a basic three part process.  First there is a pre-execution phase (here TAU (harmlessly) re-compiles the project with its compiler wrapper scripts).  Then comes the launching phase, which for the TAU plugin consists of calling the PTP's launcher normally, but substituting the TAU-instrumented executable.  Finally, after the process finishes running, the post-execution phase kicks in.  Here TAU collects and stores performance data output and cleans up any unwanted build configurations.  The generic scheme of 'things done before execution', execution and 'things done after execution' is likely to apply to most performance analysis tools, but it will be difficult to tighten up the launch delegate's interface much beyond that, given the diversity of performance analysis tools' usage requirements.  Similarly, the contents of the performance analysis launch configuration tab and any workspace options are entirely dependent on the options available to the tool in question.  Removing the TAU specific elements of the plugins would leave a serviceable shell for integration of other performance analysis tools plugins, but the plugin developers will have to do a lot of work specific to the functionality of their system.  Other issues, such as support for multiple performance analysis plugins at once, haven't received much attention yet.  I suspect the single most useful thing for the performance analysis plugin framework now would be some how-to documentation with the TAU plugin as an example.

New features added since Supercomputing include a PAPI event counter selection tool.  When PAPI is available this allows you to select PAPI counters from a checklist, which marks mutually exclusive counters as you proceed.  The selected counters are automatically defined in the project's environment.  The mechanism for selecting TAU makefiles has also been improved.  The list of check boxes for specifying TAU features is now used to narrow down a list of available makefiles, with unavailable makefile options dynamically disabled.

Upcoming changes (hopefully within the next few days) include the addition of help and usage information to the interface and improved control of performance data output and storage.

Longer range goals include improvements to the build and launch progress monitoring system, creation of a version of the TAU launcher plugin (the selective instrumentation, PAPI and profile view plugins are universal) for non-parallel programs (making two versions of the TAU launcher plugin should help with developing the general performance plugin framework), better support for the standard make system, addition of more TAU compilation and runtime options, automatic selective instrumentation calculated by analysis of previous execution profiles and support for multi-run experiment batch launching.  Please let me know if there are any features or fixes you would like to see.

I will try to submit a new version of the TAU plugins to bugzilla before Christmas.

Happy Holidays,
Wyatt Spear