Parameter
rspo/global_shm/printer_list
Short text
Size of a shared memory area that is used by the R/3 System.
Parameter Description
The parameter value determines the number of entries in a shared memory cache of the spool system, where each entry requires about 750 Bytes.
From Release 4.0, the purpose and the administration of this cache is completely new (see the Release Notes for this parameter).
In Release 4.0, the cache is used as a temporary memory space for administrative data of all work processes that process spool output requests.
The spool work processes of a server use the cache to control the “device polling” (where the status of active pool requests is repeatedly queried automatically).
For this control, you need a cache entry for each device with active spool output requests. If the cache overflows (if there is no free entry for a new active device), then there is no polling for this device. The status of the output statement concerned is set to “Ready” immediately after it is transferred to the external spool system. The output request is printed. You can still process other requests for the device concerned without any performance problems.
The cache should be dimensioned in such a way that the peak value of the output devices active at the same time can be included in the cache, where entries for temporary use must still be available.
To ensure that the number of entries specified for controlling polling actually exist, the standard value of entries is always allocated in addition to the value specified. Example: The user enters the value 400. 700 entries are actually allocated: the 400 entries that were requested by the user plus the 300 default value entries.
Use of the cache before Release 4.0
Refer to Note 19498.
Application Area
Spool
Parameter Unit
Number of list entries
Default Value
150. The default value is also automatically added again. The entry size is about 750 bytes).
You should not set a value smaller than the default value.
Who is permitted to make changes?
The customer
Operating System Restrictions
None
Database System Restrictions
None
Are other parameters affected or dependent?
Changes to this parameter have an affect on the shared memory pool 40 (ipc/shm_psize_40, 750 bytes for each entry in the printer list).
This dependency does not apply to AS/400 systems, because on AS/400 SAP caches are not merged in shared memory pools. On AS/400 systems the parameter can be changed without taking pool sizes into account.
