Troubleshooting

Improving Oracle OLTP database performance with Dell Fluid Cache for DAS
7
To accurately and systematically evaluate both the solutions, the first step was to design a baseline
configuration based on the traditional HDD-based storage. This baseline configuration was enhanced
with Fluid Cache solution. This approach allows a fair comparison of the performance merits or
demerits of Fluid Cache solution against the baseline configuration.
The following sections describe the design and reference architecture of the DAS-based storage
solutions evaluated in this study:
 Traditional HDD-based storage solution (Baseline Configuration)
 Fluid Cache for DAS-based storage solution (Fluid Cache)
Traditional HDD-based storage solution (Baseline Configuration)
This section describes the design and architecture of the traditional HDD-based storage solution that
was used as a baseline.
The goal of the baseline configuration was to illustrate the problem stated in the introduction i.e. to
architect a typical hardware configuration that illustrates the limitation of the baseline configuration
where the database performance cannot be improved by adding additional disks since the limits of the
storage controller have been reached.
Figure 1 shows this configuration. A Dell PowerEdge R720 is used as a single node database server. The
Dell PowerEdge Express Flash 350GB SLC PCIe SSDs that are factory installed with the server are not
used in the baseline performance testing. For more details on the R720 server configuration used in this
study, refer to Table 1. The server is attached to four fully populated Dell PowerVault
TM
MD1220
storage enclosures using a single Dell PERC H810 external RAID controller. The H810 is connected to the
four daisy-chained PowerVault MD1220 enclosures in unified mode
1
. In unified mode, the H810
automatically detects the redundant path and balances the I/O load through both paths to the backend
enclosures
2
.
Note: A single PERC H810 supports a maximum of four daisy-chained PowerVault MD1220s
2
.