Parameter
rspo/global_shm/printer_list

Short text
Size of a chared memory area that is used bythe R/3 System.The parameter value determines the number of entries in a sharedmemory cache of the spool system, where each entry requires about750 Bytes.From Release 4.0, the purpose and the administration of thiscache is completely new (see the Release Notes for this parameter).In Release 4.0, the cache is used as a temporary memory spacefor administrative data of all work processes that processspool output requests.The spool work processes of a server use the cache to control the"device polling" (where the status of active pool requests isrepeatedly queried automatically).For this control, you need a cache entry for each device withactive spool output requests. If the cache overflows (if there isno free entry for a new active device), then there is no pollingfor this device. The status of the output statement concernedis set to "Ready" immediately after it is transferred to theexternal spool system.The output request is printed. You can still process other requestsfor the device concerned without any performance problems.The cache should be dimensioned in such a way that the peak valueof the output devices avtive at the same time can be included inthe cache, where entries for temporary use must still beavailable.To ensure that the number of entries specified for controllingpolling actually exist, the standard value of entries is alwaysallocated in addition to the value specified. Example: Theuser enters the value 400. 700 entries are actually allocated:the 400 entries that were requested by the user plus the300 default value entries.
Use of the cache before Release 4.0
Refer to Note 19498.

Work area
Spool

Parameter unit
Number of list entries

Default value
150. The default value is also automatically addedagain. The entry size is about 750 bytes).You should not set a value smaller than the default value.

Who is allowed
The customer

Limitation for os
None

Limitation for db
NoneChanges to this parameter have an affect on the shared memeory pool40 (ipc/shm_psize_40, 750 bytes for each entry in theprinter list).This dependency does not apply to AS/400 systems, because on AS/400SAP caches are not merged in shared memory pools.On AS/400 systems the parameter can be changed without takingpool sizes into account.