An outbound queue sends data to another Replication Server
or to a data server. In these calculations the destination is called a direct destination
site.
For each database replicated to (or
through) the direct destination site, some part of the table volumes
passes through the queue. The fraction of a table replicated through
a queue is called replication selectivity.
Calculate an upper bound of the
OutboundQueueVolume by assuming the highest possible replication selectivity
of 1 (or 100 percent) for all tables. Then, add together
OutboundTableVolumes for
all tables replicated through the queue.
OutboundQueueVolumeupper= sum(OutboundTableVolumes) + OutboundTransactionVolume
For example, if two tables with
OutboundTableVolumes of
20K per second and 10K per second and an assumed
OutboundTransactionVolume of
1K per second are replicated through an outbound queue, the
OutboundQueueVolume would
be:
20K/Sec + 10K/Sec + 1K/Sec = 31K/Sec
You can obtain a more accurate measure of queue volume by
factoring in a value for replication table selectivity. The formula is:
OutboundQueueVolume = sum(OutboundTableVolume * ReplicationSelectivity) + OutboundTransactionVolume
For example, in the previous example, if only 50 percent of
the first table was replicated and 80 percent of the second table
was replicated, the
OutboundQueueVolume is:
(20K/Sec*0.5) + (10K/Sec*0.8) + 1K/Sec = 19K/Sec