18 September 2015
In a recent blog post, renowned PeopleSoft expert David Kurtz explores how to measure application server queuing
Why Should I Care About Queuing?
Queuing in the application server is usually an indicator of a performance problem, rather than a problem in its own right. Requests will back up on the inbound queue because the application server cannot process them as fast as they arrive. This is usually seen on the APPQ which is serviced by the PSAPPSRV process, but applies to other server processes too. Common causes include (but are not limited to):
- Poor performance of either SQL on the database or PeopleCode executed within the application server is extending service duration
- The application server domain is undersized for the load. Increasing the number of application server domains or application server process may be appropriate. However, before increasing the number of server process it is necessary to ensure that the physical server has sufficient memory and CPU to support the domain (if the application server CPU is overloaded then requests move from the Tuxedo queues to the operating system run queue).
- The application server has too many server processes per queue causing contention in the systems calls that enqueue and dequeue requests to and from IPC queue structure. A queue with more than 8-10 application server processes can exhibit this contention. There will be a queue of inbound requests, but not all the server processes will be non-idle.
When user service requests spend time queuing in the application server, that time is part of the users' response time. Application server queuing is generally to be avoided (although it may be the least worst alternative).
What you do about queuing depends on the circumstances, but it is something that you do want to know about.
Read the full post here.
You can hear from David on PeopleTools 8.54 for the Oracle DBA at Apps15: