JVM Memory Usage Test

This test monitors every memory type on the JVM and reports how efficiently the JVM utilizes the memory resources of each type.

Target of the test : A WebLogic Application Server

Agent deploying the test : An internal/remote agent

Outputs of the test : One set of results for every memory type on the JVM being monitored.

Configurable parameters for the test
Parameter	Description
Test Period	How often should the test be executed.
Host	The IP address of the host for which this test is to be configured.
Port	The port at which the specified host listens. By default, this is NULL.
Mode	This test can extract metrics from the Java application using either of the following mechanisms: Using SNMP-based access to the Java runtime MIB statistics; By contacting the Java runtime (JRE) of the application via JMX To configure the test to use SNMP, select the SNMP option. On the other hand, choose the JMX option to configure the test to use JMX instead. By default, the JMX option is chosen here.
JMX Port	This parameter appears only if the mode is set to JMX. Here, specify the port at which the JMX listens for requests from remote hosts. Ensure that you specify the same port that you configured in the management.properties file in the <JAVA_HOME>\jre\lib\management folder used by the target application Java Applications chapter.
JNDIName	This parameter appears only if the Mode is set to JMX. The JNDIName is a lookup name for connecting to the JMX connector. By default, this is JMXRMI. If you have registered the JMX connector in the RMI registry using a different lookup name, then you can change this default value to reflect the same.
User, Password, and Confirm Password	These parameters appear only if the Mode is set to JMX. If JMX requires authentication only (but no security), then ensure that the User and Password parameters are configured with the credentials of a user with read-write access to JMX. To know how to create this user, refer to the Java Applications chapter. Confirm the password by retyping it in the Confirm Password text box.
SNMPPort	This parameter appears only if the Mode is set to SNMP. Here specify the port number through which the server exposes its SNMP MIB. Ensure that you specify the same port you configured in the management.properties file in the <JAVA_HOME>\jre\lib\management folder used by the target application Java Applications chapter.
SNMPVersion	This parameter appears only if the Mode is set to SNMP. By default, the eG agent supports SNMP version 1. Accordingly, the default selection in the SNMPversion list is v1. However, if a different SNMP framework is in use in your environment, say SNMP v2 or v3, then select the corresponding option from this list.
SNMPCommunity	This parameter appears only if the Mode is set to SNMP. The SNMP community name that the test uses to communicate with the firewall. This parameter is specific to SNMP v1 and v2 only. Therefore, if the SNMPVersion chosen is v3, then this parameter will not appear.
UserName	This parameter appears only if the Mode is set to SNMP. This parameter appears only when v3 is selected as the SNMPVersion. SNMP version 3 (SNMPv3) is an extensible SNMP Framework which supplements the SNMPv2 Framework, by additionally supporting message security, access control, and remote SNMP configuration capabilities. To extract performance statistics from the MIB using the highly secure SNMP v3 protocol, the eG agent has to be configured with the required access privileges – in other words, the eG agent should connect to the MIB using the credentials of a user with access permissions to be MIB. Therefore, specify the name of such a user against this parameter.
Context	This parameter appears only if the Mode is set to SNMP. This parameter appears only when v3 is selected as the SNMPVersion. An SNMP context is a collection of management information accessible by an SNMP entity. An item of management information may exist in more than one context and an SNMP entity potentially has access to many contexts. A context is identified by the SNMPEngineID value of the entity hosting the management information (also called a contextEngineID) and a context name that identifies the specific context (also called a contextName). If the Username provided is associated with a context name, then the eG agent will be able to poll the MIB and collect metrics only if it is configured with the context name as well. In such cases therefore, specify the context name of the Username in the Context text box. By default, this parameter is set to none.
AuthPass	Specify the password that corresponds to the above-mentioned Username. This parameter once again appears only if the SNMPversion selected is v3.
Confirm Password	Confirm the AuthPass by retyping it here.
AuthType	This parameter too appears only if v3 is selected as the SNMPversion. From the AuthType list box, choose the authentication algorithm using which SNMP v3 converts the specified username and password into a 32-bit format to ensure security of SNMP transactions. You can choose between the following options: MD5 - Message Digest Algorithm SHA - Secure Hash Algorithm SHA224 - Secure Hash Algorithm 224 bit SHA256 - Secure Hash Algorithm 256 bit SHA384 - Secure Hash Algorithm 384 bit SHA512 - Secure Hash Algorithm 512 bit
EncryptFlag	This flag appears only when v3 is selected as the SNMPVersion. By default, the eG agent does not encrypt SNMP requests. Accordingly, the this flag is set to No by default. To ensure that SNMP requests sent by the eG agent are encrypted, select the Yes option.
EncryptType	If the EncryptFlag is set to Yes, then you will have to mention the encryption type by selecting an option from the EncryptType list. SNMP v3 supports the following encryption types: DES - Data Encryption Standard 3DES - Triple Data Encryption Standard AES - Advanced Encryption Standard AES128 - Advanced Encryption Standard 128 bit AES192 - Advanced Encryption Standard 192 bit AES256 - Advanced Encryption Standard 256 bit
EncryptPassword	Specify the encryption password here.
Confirm Password	Confirm the encryption password by retyping it here.
Timeout	This parameter appears only if the Mode is set to SNMP. Specify the duration (in seconds) within which the SNMP query executed by this test should time out in this text box. The default is 10 seconds.
Data Over TCP	This parameter appears only if the Mode is set to SNMP. By default, in an IT environment, all data transmission occurs over UDP. Some environments however, may be specifically configured to offload a fraction of the data traffic – for instance, certain types of data traffic or traffic pertaining to specific components – to other protocols like TCP, so as to prevent UDP overloads. In such environments, you can instruct the eG agent to conduct the SNMP data traffic related to the monitored target over TCP (and not UDP). For this, set this flag to Yes. By default, this flag is set to No.
Engine ID	This parameter appears only when v3 is selected as the SNMPVersion. Sometimes, the test may not report metrics when AES192 or AES256 is chosen as the Encryption type. To ensure that the test report metrics consistently, administrators need to set this flag to Yes. By default, this parameter is set to No.

Measurements made by the test
Measurement	Description	Measurement Unit	Interpretation
Initial memory	Indicates the amount of memory initially allocated at startup.	MB	The detailed diagnosis of this measure, when enabled, reveals the memory pools on the JVM, the memory type of every pool, and the memory manager managing the pool.
Used memory	Indicates the amount of memory currently used.	MB	It includes the memory occupied by all objects including both reachable and unreachable objects.
Available memory	Indicates the amount of memory guaranteed to be available for use by the JVM.	MB	The amount of Available memory may change over time. The Java virtual machine may release memory to the system and committed memory could be less than the amount of memory initially allocated at startup. Committed will always be greater than or equal to used memory.
Free memory	Indicates the amount of memory currently available for use by the JVM.	MB	This is the difference between Available memory and Used memory. Ideally, the value of this measure should be high.
Max free memory	Indicates the maximum amount of memory allocated for the JVM.	MB
Used percentage	Indicates the percentage of used memory.	Percent	Ideally, the value of this measure should be low. A very high value of this measure could indicate excessive memory consumption by the JVM, which in turn, could warrant further investigation.