Athena Developer Guide

Athena
Chapter 13 Framework services Version/Issue: 2.0.0
13.7 The Auditor Service
The Auditor Service provides a set of auditors that can be used to provide monitoring of various
characteristics of the execution of Algorithms. Each auditor is called immediately before and after each
call to each Algorithm instance, and can track some resource usage of the Algorithm. Calls that are thus
monitored are initialize(), execute() and finalize(), although monitoring can be
disabled for any of these for particular Algorithm instances. Only the execute() function monitoring
is enabled by default.
Several examples of auditors are provided. These are:
• NameAuditor. This just emits the name of the Algorithm to the Standard Message Service
immediately before and after each call. It therefore acts as a diagnostic tool to trace program
execution.
• ChronoAuditor. This monitors the cpu usage of each algorithm and reports both the total and
per event average at the end of job.
• MemoryAuditor. This monitors the state of memory usage during execution of each
Algorithm, and will warn when memory is allocated within a call without being released on
exit. Unfortunately this will in fact be the general case for Algorithms that are creating new
data and registering them with the various transient stores. Such Algorithms will therefore
cause warning messages to be emitted. However, for Algorithms that are just reading data
from the transient stores, these warnings will provide an indication of a possible memory leak.
Note that currently the MemoryAuditor is only available for Linux.
• MemStatAuditor. The same as MemoryAudotor, but prints a table of memory usage statistics
at the end.
13.7.1 Enabling the Auditor Service and specifying the enabled Auditors
The Auditor Service is enabled by the following line in the Job Options file:
// Enable the Auditor Service
ApplicationMgr.DLLs += { "GaudiAud" };
Specifying which auditors are enabled is illustrated by the following example:
// Enable the NameAuditor and ChronoAuditor
AuditorSvc.Auditors = { "NameAuditor", "ChronoAuditor" };
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