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30 Sizing and Best Practices for Online Transaction Processing Applications with Oracle 11g R2 using Dell PS Series | BP1003
A 9% increase in IOPS was observed when the memory was increased to 48 GB from the default setting of
38 GB. At the same time, the performance dropped when the memory was increased to a larger value such
as 64 GB. A slight increase in IOPS was observed until the memory setting of 54 GB. After that, no additional
improvements in performance were seen.
As illustrated in Figure 12, setting MEMORY_TARGET to a value between 50% and 60% of the total physical
memory on the database server resulted in optimal database performance for the simulated TPC-E-like
workload.
Note: Setting the MEMORY_TARGET value to 50–60% of the total memory on the server produced the
optimal performance for TPC-E-style workload on the 2-node Oracle RAC database. This value can be
treated as a guideline for tuning database memory but memory setting may vary depending on various
factors such as type of I/O workload, number of databases, and database characteristics. It is recommended
to monitor and tune the value depending on the type of I/O workload.
IOPS versus memory configuration
IOPS
6% higher
38 GB
13% lower
48 GB
64 GB