Friday, February 7, 2020

BW jobs/work processes hanging within program SAPLSENA

BW system may face a strange situation where there are many jobs or work processes hanging and obviously doing nothing. They are called zombie processes and then hanging with ABAP programs like SAPLSENA, SAPLRSSM, SAPLRSSM_LOAD, SAPLRS_G or SAPLRS_GENERAL etc. During situations like this the BW systems gets slower, loads are not being finished etc. In addition, an unusual number of locks may be observed in t-codes like SM12. Issue is that the system entered into dead lock. One may try to kill those work processes manually in t-codes like SM66, SM50 or killing jobs in SM37. However, it will not help as they start to pile up again quite soon.

Generally speaking; a reason why the system entered into such a state is that massive run of parallel delta loads caused a long wait time of locks. This can be also observer in table RSREQDONE field LOCKWAIT and in tables RSREQDONE or RSICCONT. Other symptom can be that infoproviders involved within the data loads are carrying heavy numbers of requests. Consequently, an enqueue management of the load request administration is not up to date.

To prevent such a situation the key is to have the enqueue management of the BW system always up to date. There are many points to be considered in order to achieve this. They mostly vary on BW version. But generally speaking parallel delta loads need to be kept on reasonable level same as the number of requests in the administration of the infoproviders are to be kept reasonable.
For details per particular BW version see SAP Note 1827854.

More information:
1827854 - Enqueue/Lock during parallel data loads
653996 - Analysis of lock situations

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