23 Performance Tuning

23.1.1 Host Configuration

If you only want availability and are not concerned with recovery time, then it is possible to use smaller, less equipped hosts as secondaries. However, to maximize high availability performance, ensure that all hosts in the multi-server domain are identical: same number and type of processor, same quantity of memory, same number and size of disks.

23.1.2 High Availability Input Adapter and Quality of Service

The Oracle CEP high availability input adapter is applicable to all high availability quality of service options. However, because the high availability input adapter increases performance overhead, it is not appropriate for some high availability quality of service options (such as Section 16.2.1, "Simple Failover" and Section 16.2.2, "Simple Failover with Buffering").

If you are using application time from the event then you do not need to use the input adapter. Application time from the event is always preferable from a performance standpoint.

23.1.3 High Availability Input Adapter Configuration

Consider increasing the batch-size to reduce the amount of time the primary server spends broadcasting event messages and to reduce the amount of time the secondary servers spend processing these messages.

Increasing the batch-size may increase the likelihood of missed and duplicate events if the primary fails before broadcasting an event message with a large number of events.

For more information, see Table 17-3 in Section 17.2.1.2, "High Availability Input Adapter Component Configuration File Configuration"

23.1.4 Broadcast Output Adapter Configuration

Consider decreasing the trimming-interval to reduce the amount of time the primary server spends broadcasting trimming messages and to reduce the amount of time the secondary servers spend processing these messages.

Decreasing the trimming-interval may increase recovery time as the new primary server's in-memory queue will be more out of date relative to the old primary.

For more information, see Table 17-9 in Section 17.2.3.2, "Broadcast Output Adapter Component Configuration File Configuration".

23.1.5 Oracle Coherence Performance Tuning Options

When configuring Oracle Coherence in a high-availability architecture, consider the following performance tuning options:

• Section 23.1.5.1, "Oracle Coherence Heartbeat Frequency"

• Section 23.1.5.2, "Oracle Coherence Serialization"

For more information, see "Testing and Tuning" in the Oracle Coherence Developer's Guide.