WebSphere Application Server V8.5 Administration and Configuration Guide for the Full Profile

Chapter 19. Monitoring z/OS systems 707

The WebSphere Application Server monitoring tools rely primarily on information gathered

from two core data infrastructures:

 Performance Monitoring Infrastructure (PMI), which is a collection of statistical agents

scattered throughout the application server that gather statistical data on the performance

of the application server components. For additional information, refer to the information

center at the following website:

http://pic.dhe.ibm.com/infocenter/wasinfo/v8r5/index.jsp?topic=%2Fcom.ibm.websp

here.zseries.doc%2Fae%2Fcprf_pmidata.html

 Request metrics, which are primarily a set of timing agents that track a request as it

navigates the components of the application server. A key differentiation of request

metrics is that they are measured at the request level. The focus of a request metric is to

record the time spent by individual requests in different components of the application and

at the end of the request, provide a record of where the time was spent in the request. For

additional information, refer to the information center at the following website:

http://pic.dhe.ibm.com/infocenter/wasinfo/v8r5/index.jsp?topic=%2Fcom.ibm.websp

here.zseries.doc%2Fae%2Ftprf_monitoringappflow.html

Other information structures on which WebSphere Application Server V8.5 monitoring tools

rely are:

 WebSphere Application Server for z/OS relies on Work Load Manager (WLM) to collect

some of the accounting and performance data.

 Resource Measurement Facility (RMF) and System Management Facility (SMF) records

to provide accounting and performance information to WebSphere.

19.2 Monitoring from the administrative console

The PMI and request metrics tools can be used from the administrative console to monitor

WebSphere Application Server for z/OS. For more information, see the following sections in

Chapter 16, “Monitoring distributed systems” on page 553:

 16.2, “Enabling monitoring infrastructures” on page 555

 16.3, “Viewing the monitoring data” on page 567

 16.4, “Monitoring examples” on page 575

19.2.1 PMI Monitoring

Performance Monitoring Infrastructure (PMI) can monitor each layer in the entire application

flow from web server, web container, EJB container, and data source.You can view the

process response time that is monitored by request metrics, through the Application

Response Measurement (ARM) interface and system log files.

PMI is used for monitoring at run time, and it has no correlation with data across different

layers. You need to enable third-party logging and then all logs need to be analyzed together

to find the details for particular transactions. This helps to identify the bottleneck layer and

response time for each and every layer, and can be analyzed. You get to know which layer is

taking maximum time for transaction processing, and based on application behavior further

actions can be taken.

708 WebSphere Application Server V8.5 Administration and Configuration Guide for the Full Profile

For additional information about the request metrics, refer to the information center at the

following website:

http://pic.dhe.ibm.com/infocenter/wasinfo/v8r5/index.jsp?topic=%2Fcom.ibm.webspher

e.zseries.doc%2Fae%2Fcprf_requestmetrics.html

19.2.2 Monitoring Dynamic Caching

Install the CacheMonitor.ear in the administrative console, which provides the GUI for

monitoring cache information at runtime. Manipulation of data is possible through the cache

monitor. At times there can be information in the cache, which can cause junk data transfers

to users, which is more applicable in heavy content applications. You can use this feature to

monitor and clear the data as required.

For additional information about working with the cache monitor, refer to the information

center at the following website:

http://pic.dhe.ibm.com/infocenter/wasinfo/v8r5/index.jsp?topic=%2Fcom.ibm.webspher

e.zseries.doc%2Fae%2Fwelc6tech_dyn_mon.html

19.2.3 Monitoring web services through PMI

There are specific APIs available for monitoring. To enable PMI for web services:

1. In the administrative console, go to Monitoring and Tuning  Peformance Monitoring

Infrastructure, shown in Figure 19-2.

Figure 19-2 Selecting PMI level

2. Select custom  web services. Select the boxes that are required to cover the business

requirement of monitoring according to the application, as shown in Figure 19-3 on

page 709.