Tuning the Cluster Interconnect - Expert Oracle RAC Performance Diagnostics and Tuning - page 458

The statistics collected will give directions as to where the performance concerns may be: the prepare phase
or the transfer phase. If the statistics on the transfer phase are significantly on the higher side, causing concern, for
obvious reasons the interconnect configuration and setup may have to be looked at. However, if the prepare phase is
of concern, the root cause of the problem should be identified by looking at what is causing these high numbers. The
reasons could be resource contention, lack of resources, or the process is simply waiting or hung.

■ We discussed the concerns around the prepare phase in Chapter 13. in this chapter, we just focus on the
transfer phase.

Note

Workshop
Figure 14-5 illustrates a six-node RAC cluster running a mixed distributed workload system. The cluster contains two
separate databases, and the servers have been logically partitioned using server pools.

Database 1 Database 2

Node 1 Node 2 Node 3 Node 4 Node 5 Node 6

SSKY1 SSKY2 SSKY3 SSKY4 SSKY5 SSKY6

AV7 AV8 AVL9 AV10 AV11 AV12 AV13 AV14 AV15 AV16

GRID_DATA PRD_DATA

Figure 14-5. Six-node RAC cluster - Distributed Workload

Users have been complaining about poor performance of the cluster and the DBA's look at the general health of
the database and analyze the environment.