What is request metrics?
Request metrics lets you to track individual transactions, recording the processing time in each of the major WAS components.
Output can be saved to...
- Log files
- Application Response Measurement (ARM) agents
Output looks similar to....
HTTP request/trade/scenario ------------------------------> 172 ms Servlet/trade/scenario -----------------------------> 130 ms EJB TradeEJB.getAccountData ---------------------> 38 ms JDBC select --------------------------------> 7 msTransaction flow response times are collected for...
- Web server plug-in
- Web container
- EJB container
- back end database
For example, the response time for the servlet, which is 130 milliseconds, also includes 38 milliseconds from the enterprise beans and Java Database Connectivity. Therefore, 92 ms can be attributed to the servlet process. Tools can inject synthetic transactions to test the performance of the system.
Request metrics can also be used as an alert mechanism to detect when the performance of a particular request type goes beyond acceptable thresholds.
Request metrics performance overhead can be mitigated by the use of filters...
- Source IP filter
- URI filter
- EJB method name filter
- JMS parameters filter
- Web services parameters filter
When filtering is enabled, only requests that match the filter...
- generate request metrics data
- create log records
- call the ARM interfaces
We can inject work into a running system generate trace information and to evaluate the performance of specific types of requests in the context of a normal load, ignoring requests from other sources that might be hitting the system.
Filters are only applicable where the request first enters WAS.
Related tasks
Data we can collect with request metrics
Monitor application flow
Related
Example: Using request metrics