Module: startInitCommDiags¶

This module defines config params that allow observing inter-locale communication during module initialization and teardown.

It is hard for a programmer to determine exactly what happens during initialization or teardown of a module, because the code that runs then does so implicitly, as a result of the declarations present. And even if that code can be identified, doing debug output or logging data for later reporting might not work because the Chapel capabilities needed to do so could be unavailable due to being implemented by built-in modules which themselves are not yet initialized, or have already been torn down.

This module is designed to help with that problem, by providing built-in support for doing on-the-fly reporting and/or background counting of inter-locale communication operations during module initialization and teardown. To use it, set either or both of the config params below using appropriate -sconfigParamName=value command line options when you compile your program.

The reporting and/or counting enabled by this module covers all of program execution, from just before the first module is initialized until just after the last one is torn down. This is almost always a superset of the part of the program that is of interest, which is often just a single module. To learn what communication is being done by a single module during its initialization and teardown it is usually necessary to run a small test program twice, once with the module present and once without it.

Note: It is not necessary to use this module. It is included in every program automatically. Using compiler command line options to set the config params it provides is the only way to interact with it.

config param printInitVerboseComm = false¶

If this is set, on-the-fly reporting of communication operations will be turned on before any module initialization begins and turned off after all module teardown ends. See module CommDiagnostics and its procedures startVerboseComm and stopVerboseComm for more information.

config param printInitCommCounts = false¶

If this is set, communication operations are counted from before any module initialization begins until after all module teardown ends, and then the aggregate counts are printed. See module CommDiagnostics and its procedures startCommDiagnostics, stopCommDiagnostics, and getCommDiagnostics for more information.