PMI data counters

Counters are enabled at the module level and can be enabled or disabled for elements within the module. Each counter has a specified monitoring level: low, medium, high or maximum. Data collection can affect performance of the application server. The impact depends on the number of counters enabled, the type of counters enabled and the monitoring level set for the counters.

Tivoli Performance Viewer collects and reports performance data for these PMI counters:

• Enterprise bean module --> Enterprise bean --> Methods in the bean
  Data counters for this category provide information about enterprise beans, enterprise bean methods, and the remote interfaces that enterprise beans use. Some examples of this information are:
  • The average number of active beans
  • The number of times bean data is loaded or written to the database
  • The number of times a method is called
  • The average response time for a method
  • The number of calls that attempt to retrieve an object from a pool
  • The number of times an object is found in a pool

  For more information about these counters, see BeanModule data counters.

• JDBC connection pools
  Data counters for this category provide information about connection pools for a database. Some examples of this information are:
  • The average size of the connection pool or number of connections
  • The average number of threads waiting for a connection
  • The average wait time in milliseconds for a connection
  • The average time the connection is in use

  The counters collect performance data for JDBC data sources for versions 4 and 5 of WebSphere Application Server. This information is located under JDBC Connection Pool data contents. For a version 4 data source, the data source name is used. For a version 5 data source, the JNDI name is used. For more information about these counters, see JDBC connection pool data counters.

• J2C connection pool
  Data counters for this category provide usage information about the Java 2 Enterprise Edition (J2EE) Connector Architecture. This architecture enables managed connections to various resources such as data sources and JMS resources, as well as procedural back-end systems, such as Customer Information Control System (CICS), and Information Management System (IMS). For more information about these counters, see J2C connection pool data counters.

• Java Virtual Machine API (JVM)
  Data counters for this category provide information about the memory that a process uses, as reported by Java Virtual Machine (JVM) run time. Some examples of this information are:
  • The total memory available
  • The amount of free memory for the JVM

  The JVM run time also includes data from the Java Machine Profiler Interface (JVMPI). This data provides detailed information about the JVM running the application server. JVMPI is supported on V5R2 and higher. For more information about these counters, see Java Virtual Machine data counters.

  Notes:
  
  • The instructions at the top of the help topic do not apply to iSeries. To enable JVMPI, see Enable Java Virtual Machine Profiler Interface (JVMPI) data reporting.
  • The total memory counter in the Java Virtual Machine (JVM) data category is a BoundedRangeStatistic type. However, the upperBound and lowerBound are not implemented in WebSphere Application Server Version 5.
  • Use JVMPI data can have a significant impact on the performance of your application server. The JVMPI data counters are enabled only when the PMI event JVMRunTimeModule is set to Max.

• Servlet session manager
  Data counters for this category provide information about HTTP sessions. Some examples of this information are:
  • The total number of accessed sessions
  • The average amount of time it takes for a session to perform a request
  • The average number of concurrently active HTTP sessions

  For more information about these counters, see Session data counters.

• Thread pool
  Data counters for this category provide information about the thread pools for Object Request Broker (ORB) threads and the Web container pools used to process HTTP requests. Some examples of this information are:
  • The number of threads that are created and destroyed
  • The maximum number of pooled threads that are allowed
  • The average number of active threads in the pool

  For more information about these counters, see ThreadPool data counters.

• Java Transaction API (JTA)
  Data counters for this category provide information about the transaction manager. Some examples of this information are:
  • The average number of active transactions
  • The average duration of transactions
  • The average number of methods per transaction

  For more information about these counters, see Transaction data counters.

• Web applications --> Servlet
  Data counters for this category provide information about the selected server. Some examples of this information are:
  • The number of loaded servlets
  • The average response time for completed requests
  • The number of requests for the servlet

  For more information about these counters, see Web application data counters.

• Object Request Broker (ORB)
  Data counters for this category provide information about the ORB. Some examples of this information are:
  • The object reference lookup time
  • The total number of requests
  • The processing time for each interceptor

  For more information about these counters, see Object Request Broker data counters.

• Web Services Gateway (WSGW)
  Data counters for this category provide information about WSGW. Some examples of this information are:
  • The number of synchronous requests and responses
  • The number of asynchronous requests and responses

  For more information about these counters, see Web service gateway (WSGW) data counters.

• System data
  Data counters for this category provide information about a machine (node), such as CPU utilization and memory usage. Due to the design of iSeries architecture, there is no direct mapping of free system memory. Thus, the value of system free memory returns a value zero. Note that this category is available at node level, which means it is only availabe at NodeAgent in WebSphere Application Server Network Deployment. For more information about these counters, see System data counters.

• Workload Management (WLM)
  Data counters for this category provide information about workload management. Some examples of this information are:
  • The number of requests
  • The number of updates
  • The average response time

  For more information about these counters, see Workload Management data counters.

• Dynamic cache
  Data counters for this category provide information about the dynamic cache service. Some examples of this information are:
  • The memory cache size
  • The number of invalidations
  • The number of hits and misses

  For more information about these counters, see Dynamic cache data counters.

• Web services
  Data counters for this category contain information for Web services. Some examples of this information are:
  • The number of loaded Web services
  • The number of requests delivered and processed
  • The request response time
  • The average size of requests

  For more information about these counters, see Web services data counters.