Advantages and disadvantages of the method of buffer synchronization:The load on the network is kept to a minimum. If the buffers were to be synchronized immediately after each modification, each server would have to inform all other servers about each modification to a buffered table via the network. This would have a negative effect on the performance.
The local buffers of the application servers can contain obsolete data between the moments of synchronization.This means that:
Only those tables which are written very infrequently (read mostly) or for which such temporary inconsistencies are of no importance may be buffered.Tables whose entries change frequently should not be buffered. Otherwise there would be a constant invalidation and reload, which would have a negative effect on the performance.
DATA CONSISTENCY IN ABAP DAY 14
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SAP BW information and reporting tools
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