Cover topics that are relevant when changing the number of work processes (increase or decrease) of an instance, also considering Operation Modes (transaction RZ04).
This WIKI page will list topics that should be considered when the number of work processes of an instance would be changed.
The system has an application server with the following work processes configured:
|Type||Number of processes|
|Update V2 (UP2)||2|
The "day" operation mode has the same work process distribution as the table above.
The "night" operation mode switches 5 dialog work processes to background processes.
The number of spool work processes has to be increased to 4 and both operation modes will have 4 spool work processes.
Following the example above, you would edit the instance profile of the related application server and would change the parameter "rdisp/wp_no_spo" from 2 to 4.
You would then restart the SAP instance and adjust the operation modes accordingly.
Issues can occur if the operation modes are not adjusted right after the instance was restarted (e.g., before the first operation mode switch should occur).
1. DYNAMIC WORK PROCESSES
As of the SAP NetWeaver 7.0 EHP2 and the SAP kernel release 720, the system can have Dynamic Work processes.
The SAP kernel 72x is downward compatible to previous NetWeaver releases and customers are encouraged to upgrade the kernel to 72x, since previous kernel releases are not supported anymore (see the SAP notes listed at the "Related Content" section, below).
Therefore, the parameter "rdisp/wp_max_no" has to be manually adjusted whenever the number of work process will change, if the kernel 72x is being used as downward compatible kernel (e.g., NetWeaver releases prior to 7.0 EHP2).
2. APPC AND WP BLOCKS
There are memory blocks required by the work process and other processes (like the Dispatcher and the Gateway) in order to operate.
Whenever the number of work processes is changed, the parameters mentioned at the SAP note 3223 have to be adjusted as well.
As of the SAP kernel 740, the parameter "rdisp/appc_ca_blk_no" does not exist anymore.
In addition, the kernel 74x has a new functionality of using formulas to define the parameters' values.
Thus, if the parameter "rdisp/wp_ca_blk_no" is not set, it is not required to set it manually as the default value (formula) will calculate the appropriate value when the system starts.
3. STANDALONE ENQUEUE
If the system has a Standalone Enqueue ("ENSA") running (at an ASCS instance), consider revising the parameter "enque/server/max_clients" (SAP note 1002075, SAP KBA 2196513) and the parameters mentioned at the SAP note 920979.
Related SAP Notes/KBAs
SAP note 1716826: Usage of the downward compatible kernel 721 (EXT)
SAP note 1713986: Installation of kernel 721 (EXT)
SAP note 2133909: Usage of kernel 722 (EXT)
SAP note 2115344: Installation of Kernel 722 (EXT)
SAP note 3223: Number of WP and APPC blocks
SAP note 920979: Out of memory in the standalone enqueue server
SAP note 1002075: Too many enqueue clients in standalone enqueue server
SAP KBA 2196513: WARNING => NiICreateHandle: no more free handles (XXXX)