Caché Monitoring Guide - InterSystems Documentation

7
Examining Routine Performance Using
^%SYS.MONLBL
The routine ^%SYS.MONLBL provides a user interface to the Caché MONITOR facility. This utility provides a way to
diagnose where time is spent executing selected code in Caché ObjectScript and Caché Basic routines, helping to identify
lines of code that are particularly resource intensive. It is an extension of the existing MONITOR utility accessed through
^PERFMON and the %Monitor.System package classes. Because these utilities share the same memory allocation, you
can only run one of them at a time on a Caché instance.
This chapter contains the following sections:
• Invoking the Line-by-line Monitoring Routine
• Line-by-line Monitoring Options
• Sample Line-by-line Monitor Reports
• Line-by-line Monitor Programming Interface
7.1 Invoking the Line-by-line Monitoring Routine
If the monitor is not running when you invoke ^%SYS.MONLBL, the routine displays a warning message and gives you
the option to start the monitor or to check memory requirements. For example:
%SYS>Do ^%SYS.MONLBL
WARNING ! Starting the line-by-line monitor will enable the
collection of statistics for *every* line of code executed by
the selected routines and processes. This can have a significant
impact on the performance of a system, and it is recommended
that you do this on a 'test' system.
The line-by-line monitor also allocates shared memory to track
these statistics for each line of each routine selected. This is
taken from the general shared memory already allocated by Cache and
should be considered if you are using '*' wildcards and trying to
analyze a large number of routines. If the monitor fails to start due
to a problem with memory allocation, you may need to increase the
GenericHeapSize parameter in the system configuration. You may use
the 'Memory Requirements' option to see how much memory a collection
would need (without starting the collection).
1.) Start Monitor
Caché Monitoring Guide 57