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A system monitor (SM) in systems engineering is a process within a distributed system for collecting and storing state data. This is a fundamental principle supporting Application Performance Management. Contents [hide] * 1 Overview * 2 System monitor basics * 2.1 Protocol * 2.2 Data access * 2.3 Mode * 3 References
The argument that system monitoring is just a nice to have, and not really a core requirement for operational readiness, dissipates quickly when a critical application goes down with no warning. The configuration for the system monitor takes two forms: 1. configuration data for the monitor application itself, and 2. configuration data for the system being monitored. See: System configuration The monitoring application needs information such as log file path and number of threads to run with. Once the application is running, it needs to know what to monitor, and deduce how to monitor. Because the configuration data for what to monitor is needed in other areas of the system, such as deployment[disambiguation needed], the configuration data should not be tailored specifically for use by the system monitor, but should be a generalized system configuration model. The performance of the monitoring system has two aspects:
* Impact on system domain or impact on domain functionality: Any element of the monitoring system that prevents the main domain functionality from working is in-appropriate. Ideally the monitoring is a tiny fraction of each applications footprint, requiring simplicity. The monitoring function must be highly tunable to allow for such issues as network performance, improvements to applications in the development life-cycle, appropriate levels of detail, etc. Impact on the systems' primary function must be considered. * Efficient monitoring or ability to monitor efficiently: Monitoring must be efficient, able to handle all monitoring goals in a timely manner, within the desired period. This is most related to scalability. Various monitoring modes are discussed below. There are many issues involved with designing and implementing a system monitor. Here are a few issues to be dealt with: * configuration
* data access
System monitor basics 
There are many tools for collecting system data from hosts and devices using the SNMP (Simple Network Management Protocol).Most computers and networked devices will have some form of SNMP access. Interpretation of the SNMP data from a host or device requires either a specialized tool (typically extra software  from the vendor) or a Management information base (MIB), a mapping of commands/data references to the various data elements the host or device provides. The advantage of SNMP for monitoring is its low bandwidth requirements and universal usage in the industries. Unless an application itself provides a MIB and output via SNMP, then SNMP is not suitable for collecting application data. Other protocols are suitable for monitoring applications, such as CORBA (language/OS-independent), JMX (Java-specific management and monitoring protocol), or proprietary TCP/IP or UDP protocols (language/OS independent for the most part). Data access 
Data access refers to the interface by which the monitor data can be utilized by other processes. For example, if the system monitor is a CORBA server, clients can connect and make calls on the monitor for current state of an element, or historical states for an element for some time period. The system monitor may be writing data directly into a database, allowing other processes to access the database outside the context of the system monitor. This is dangerous however, as the table design for...
References: based on their personal experiences (von Glasersfeld, 1984). From this
paradigm, conceptual development occurs when people become dissatisfied
with their existing conceptions (a state known as "disequilibration"; see Piaget
1952, 1969) and feel the need to modify their understanding of the world.
memory, and, finally, modifying existing knowledge structures in long-term
memory (Atkinson & Shiffrin, 1968).
activities that a) help students become aware of their prior knowledge and the
ways in which this knowledge develops over time (Hewson & Thorley, 1990),
and b) surprise or perplex students in order to have them experience
dissatisfaction with this knowledge (Dykstra, Boyle, & Monarch, 1992).
efficiency (Reif & Larkin, 1991) and the differences between the knowledge
structures and thought processes of experts and novices (Chi, Feltovich, &
Glaser, 1981; Larkin, McDermott, Simon, & Simon, 1980).
learning environment. Strike and Posner (1992), for instance, argue that their
well-known outline of the conditions necessary for conceptual change
& Hertzog, 1982) should be expanded to include institutional and social3
sources of motivation and goals
Cobb, Wood, & Yackel, 1993) . For instance, students are often reticent to
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