I'm evaluating the performance of Guided procedures, in SAP Netweaver version 7.05 SP1. It runs over a machine with Intel Xeon @ 2.13 Ghz, 3.37 GB RAM, 2046 MB swap size, Windows Server 2003 Enterprise Edition, Service Pack 1, JRE version 1.5.0_11. The maximum JVM heap size is 1024 MB, using a parallel young garbage collection policy (-XX:+UseParNewGC), I'm using the parameter -XX
:+HandlePromotionFailure in order to work around the bug 6226790 related to the UseParNewGC garbage collection option (http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=6226790).
The test target is a "dummy" process, with one sequential block and three actions. The load is generated with JMeter, the test script creates a process instance, issuing a HTTP request to the corresponding URL. The load test consists in a increasing load of 1 to 20 concurrent virtual users, with a ramp-up time of 20 minutes (one new user every minute). The virtual users start process instances until the test is stopped (there is no defined iteration number), with a think time of 10 seconds.
Till a load of 10 concurrent users the behavior is normal: constant response time about 500 ms and increasing throughput (considering the throughput as process instances started per second), until that moment about 300 process instances are created. However, as the test continues, the response time suddenly increases, the throughput falls and eventually the netweaver instance gets stuck. What is curious is that, although the netweaver instance is stuck, the utilization of the processor is low (less than 10%), as well as the memory (the heap just grows till 610 MB, its limit is 1024 MB). There are no sign of exhaustion of other resources, according to the corresponding performance counters (disk read and write queues, network utilization, context switches per second).
The GP runtime is using the local workflow engine, the test has been repeated with 2, 4 and 8 threads in the workflow engine. In all the cases the above described results were almost the same.
Does anybody know why the netweaver instance gets stuck under such conditions, and is there a way to solve this problem?
Thanks in advance
Edited by: Alexander Ambriz on Jan 13, 2008 4:34 PM