Concepts

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Concepts

All MyARM supported ARM 4.0 language binding agents and analysis tools use the following concepts.

Configuration

The adaption of the MyARM agent to the current hard- and software environment is done using a set of configuration files. Each file contains name-value pairs, so-called configuration properties. For example setting the basic.time.use_utc property to true will instruct MyARM to show time information only in UTC.

basic.time.use_utc = true

For more and detailed information read the configuration chapter.

All MyARM agents and tools are using the MYARM_CONFIG_URL environment variable to get the configuration file.

Logging

The ARM standard is designed to transparently plugin into an instrumented application. Also, the ARM agent should never interfere with the application. The MyARM ARM agent uses log messages to report the current configuration, state changes, warnings and errors. The log messages can be written to different kinds of output media such as normal files, Windows event log or Unix syslog.

MyARM supports the following levels of log messages:

error
Error log messages to report errors
warning
Warning log messages to report some unusual situations
status
Status log messages to report state changes within the ARM agent
info
Only informational messages
config
Logs the configuration used by the ARM agent

For more information read the section "Configuring Log facility".

ARM data buffer

When executing an instrumented application measured and recorded ARM data is serialized and written to a so-called ARM data buffer. Therefore such an ARM data buffer can contain any kind of data like transaction response time measurements, log messages or even other kind of data like CPU utilization.

An ARM data buffer has a defined size in bytes which can be specified by a configuration property. Avoiding memory shortage due to a high rate transaction measurements, a maximum number of allocated ARM data buffers is defined. For more detailed information about configuring the ARM data buffer concept read the configuration properties section.

Handler

A handler is a technical concept for implementing filters, monitors or calculators for transaction measurements. It is used to process a measured transaction instance according to the current runtime configuration or performs additional tasks such as sending an auto response message for event flow measurements.

For a detailed description of all features implemented by handler read section handler.

Datasink

The datasink concept is used to transport and store any kind of measured and recorded ARM data in a consistent way. Datasinks within MyARM are plugins which are loaded during initialization phase according to the current configuration.

With this concept it is possible to use a chain of datasinks which will:

  1. store any measured data onto disk (filesink)
  2. read the measured data from the disk and send it to a central server using TCP/IP (tcpsink)
  3. finally storing the measured data into a MySQL database (mysqlsink).

For a detailed description of all available datasinks read section datasinks.

Datasource

The datasource concept defines a consistent interface to read in and manage recorded ARM data stored in a database. Like datasinks they are implemented as plugins which are loaded during runtime. Each analysis tool uses this datasource concept to retrieve the measured ARM data from the database. A datasource exists for each supported database as described in section Databases.

Resource watchdog

During deployment MyARM needs some resources (mainly memory) to operate correctly. The amount of memory needed depends highly on the number and frequency of transaction measurements. However MyARM should never interfere with expend the resources of the deployed application. Therefore MyARM provides various configuration properties to limit the amount of used resources. To monitor the used resources by MyARM the resource watchdog provides a simple mechanism to log the used resources.

The resource watchdog can be separately configured for monitoring of resources of following programs: