Troubleshooting

Improving Oracle OLTP database performance with Dell Fluid Cache for DAS

Architecture: Baseline configuration Figure 1.

As shown in Figure 1, eight virtual disks (VDs) were configured for Oracle data files and four VDs were

configured for Oracle Flash Recovery Area (FRA) across the four enclosures. Twelve disks were

configured as global hot spares to ensure that there is at least one hot spare for each of the twelve VDs

used for Oracle database. The VDs used for the Oracle data files were configured with eight disks in

RAID10. The VDs used for FRA were configured as RAID5 with 4+1 disks. These RAID levels were

configured based on Dell’s recommendation and best practices for Oracle OLTP database

. For more

details on the VD configuration, refer to Table 4.

The database server was configured in accordance with Dell’s standard best practices on installing

single node single instance Oracle 11gR2 databases

Automatic Shared Memory Management (ASMM) was enabled and the sga_target and

sga_max_size ASMM parameters were both set to 8GB. This size of the System Global Area (SGA)

allows the database to stress the storage disks by generating more physical I/Os than logical I/Os from

the main memory.

Each of the VDs created on the backend storage for the Oracle database was added as an Automatic

Storage Management (ASM) disk to its respective ASM disk group. Figure 1 shows the following two

Oracle ASM disk groups created on the backend storage:

 DATA_DG ― contains Redo Log Groups, Undo tablespace, Temp tablespace, Quest tablespace

(for TPC-C schema) and other seed database tablespaces

 FRA_DG ― contains Archive logs and Flashback logs