Deleting an Oracle HTTP Server Component

5-2 Oracle Fusion Middleware Administrators Guide for Oracle HTTP Server processes, it is best to configure the server to start enough child processes initially so that requests can be handled without having to spawn more child processes.

5.1.2 Single Unit Process Model

Oracle HTTP Server provides functionality that allows it to terminate as a single unit if the parent process fails. The parent process is responsible for starting and stopping all the child processes for an Oracle HTTP Server instance. The failure of the parent process without first shutting down the child processes leaves Oracle HTTP Server in an inconsistent state that can only be fixed by manually shutting down all the orphaned child processes. Until all the child processes are closed, a new Oracle HTTP Server instance cannot be started because the orphaned child processes still occupy the ports the new Oracle HTTP Server instance needs to access. To prevent this from occurring, the DMS instrumentation layer in child processes on UNIX and monitor functionality within WinNT MPM on Windows monitor the parent process. If they detect that the parent process has failed, then all of the remaining child processes are shut down. When this functionality is combined with OPMN, it means that Oracle HTTP Server is easily restarted in case of a parent process failure. The DMS instrumentation layer on UNIX and a monitor within WinNT MPM on Windows ensures that all of the Oracle HTTP Server child processes are shut down, leaving the ports open for a new Oracle HTTP Server instance. OPMN ensures that a new instance is started once the failure of the original instance is detected.

5.2 Monitoring Oracle HTTP Server Performance

Oracle Fusion Middleware automatically and continuously measures run-time performance for Oracle HTTP Server. The performance metrics are automatically enabled; you do not need to set options or perform any extra configuration to collect them. If you encounter a problem, such as an application that is running slowly or is hanging, you can view particular metrics to find out more information about the problem. Note that Fusion Middleware Control provides real-time data. If you are interested in viewing historical data, consider using Grid Control.

5.2.1 Viewing Oracle HTTP Server Performance Metrics

You can view metrics from the Oracle HTTP Server home menu of Fusion Middleware Control: 1. Select the Oracle HTTP Server that you want to monitor. The Oracle HTTP Server home page is displayed.

2. From the Oracle HTTP Server menu, choose Monitoring, and then select

Performance Summary . The Performance Summary page is displayed. It shows performance metrics, as well as information about response time and request processing time for the Oracle HTTP Server instance.

3. To see additional metrics, click Show Metric Palette and expand the metric

categories. Tip: Oracle HTTP Server port usage information is also available from the Oracle HTTP Server home menu. Managing and Monitoring Server Processes 5-3 The following figure shows the Oracle HTTP Server Performance Summary page with the Metric Palette displayed:

4. Select additional metrics to add them to the Performance Summary.

5.2.2 Understanding Oracle HTTP Server Performance Metrics

This section lists some of the most commonly-used metrics that can help you analyze Oracle HTTP Server performance. OHS Server Metrics The OHS Server Metrics folder contains performance metric options for Oracle HTTP Server. The following table describes the metrics in the OHS Server Metrics folder: Element Description CPU Usage CPU usage and idle times Memory Usage Memory usage and free memory, in MB Processes Busy and idle process metrics Request Throughput Request throughput, as measured by requests per second Request Processing Time Request processing time, in seconds Response Data Throughput Response data throughput, in KB per second Response Data Processed Response data processed, in KB per second Active HTTP Connections Number of active HTTP connections Connection Duration Length of time for connections HTTP Errors Number of HTTP 4xx and 5xx errors