Troubleshooting

Optimizing an Oracle Database with Dell Compellent Automated Tiered Storage
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2,200 concurrent users in an increment of 100. Test metrics include transaction per second (TPS) and
average transaction response time in seconds. Test results are discussed in the Test Results section
below.
Enabling Data Progression and simulating read-only workload
Following the TPC-C test of the baseline configuration, Data Progression and Data Instant Replay are
enabled on the Oracle storage volumes except the REDO volumes. As discussed in the previous section
Oracle Database with Dell Compellent Data Progression, Oracle online redo log files benefit most from
placing on the 15K RPM SAS or Fibre Channel storage tier. Therefore, for our test, the 4 REDO volumes
remain on the 15K RPM SAS drives with RAID 10 configuration. Data Instant Replay is not enabled on
the 4 REDO volumes. The 4 DATA volumes and the 4 FRA volumes are grouped together in a
consistency group with a scheduled daily Data Instance Replay.
The Data Progression storage profile assigned to the DATA volumes and the FRA volumes are shown in
Table 2. In this configuration, the DATA volumes span on all 3 tiers of the storage. The FRA volumes
span on tier 2 and tier 3 storages.
Table 2. Oracle volume placement with Data Progression
Writeable Data
Replay Data
Tier 1 SSD
RAID 10
DATA disk group volumes
RAID 5-5
DATA disk group volumes
Tier 2 15K RPM SAS
RAID 10
DATA disk group volumes,
FRA disk group volumes
RAID 5-9
DATA disk group volumes
Tier 3 7K RPM SAS
RAID 10-DM
RAID 6-10
DATA disk group volumes,
FRA disk group volumes
Dell Compellent storage continuously captures user characteristics of each data block including
creation time, location, access frequency, and data type. This data enables Data Progression to
determine what data pages should be moved to a different storage tier or a different RAID level within
an existing tier. In order to generate sufficient IO activities to enable Data Progression data
movement, a read-only Oracle TPC-C workload was conducted on the test environment during a five
day period. The purpose of the read-only TPC-C workload includes:
 Read-only stress load doesn’t make any data updates. The original data set is preserved for the
post Data Progression TPC-C performance test, which can enable an apple-to-apple comparison
with the baseline configuration.
 Read-only stress load can generate sufficient IO activities on the storage array and in turns creates
access frequency of data blocks.
 The mostly read and write database objects represented by the read-only TPC-C workload and the
typical TPCC workload (30% writes and 70% reads) are almost identical. This enables the read-only
TPCC workload to generate the same type of data access frequency as the typical TPC-C workload,
so Data Progression can move the correct data set for the post Data Progression TPC-C test.
Tiered storage configuration with Data Progression
At the end of the read-only stress load, the Oracle database volumes which were assigned with Data
Progression storage profiles have shown significant data redistributions among storage tiers and RAID