Higher I/O bandwidth available, because both disk groups are spread over all available spindles. The ratio for the size of the inner and outer partitions depends on the estimated size of the database area and the flash recovery area. It requires partitioning each disk into two partitions: a smaller partition on the faster outer portion of each drive for the database area, and a larger partition on the slower inner portion of each drive for the flash recovery area. The second option is illustrated in Figure 2-2. Enable Oracle managed files by setting initialization parameters DB_CREATE_FILE_DEST, DB_RECOVERY_FILE_DEST, and DB_RECOVERY_FILE_DEST_SIZE:ĭescription of "Figure 2-2 Partitioning Each Disk" To simplify file management, use Oracle managed files to control file naming. The flash recovery area contains recovery-related files, such as a copy of the current control file, a member of each online redo log file group, archived redo log files, RMAN backup sets, and flashback log files. The database area contains active database files, such as datafiles, control files, online redo log files, Data Guard Broker metadata files, and change tracking files used for RMAN incremental backups. When using ASM for database storage, you should create two disk groups: one disk group for the database area and another disk group for the flash recovery area: Although ASMLib is not required to run ASM, it simplifies the management of disk device names, makes the discovery process simpler, and removes the challenge of having disks added to one node and not be known to other nodes in the cluster.Ģ.1.3 Use a Simple Disk and Disk Group Configuration ASMLib eliminates the impact when the mappings of disk device names change upon system reboot. To improve manageability, ASMLib should be used on platforms where it is available. This approach is particularly well suited for introducing low-cost storage into an existing environment where traditional storage configurations currently exist. However, ASM can be phased into your environment initially supporting only the flash recovery area. ASM also enables low-cost modular storage to deliver higher performance and greater availability by supporting mirroring as well as striping.ĪSM should be used to manage all database files. ASM helps manage a dynamic database environment by letting you grow the database size without shutting down the database to adjust the storage allocation.
TIMEPLUS NETWORK CONFIGURATION MANUAL
It extends the concept of stripe and mirror everything (SAME) to optimize performance, while removing the need for manual I/O tuning (distributing the datafile layout to avoid hot spots). The flash recovery area can be configured to use low-cost storage while the database area remains on traditional storage.Ģ.1.2 Use Automatic Storage Management (ASM) to Manage Database FilesĪSM is a vertical integration of both the file system and the volume manager built specifically for Oracle database files. Because the flash recovery area contains recovery related files that are typically accessed with sequential 1MB streams, the performance characteristics of low-cost storage are well suited for the flash recovery area. The Oracle Database flash recovery area is an ideal candidate for low-cost storage. The O racle Resilient Low-Cost Storage Initiative is designed to help customers reduce IT spending and promote use of low-cost storage arrays in both departmental and enterprise environments. However, low-cost storage arrays do not have better I/O rates for OLTP type applications than traditional storage, although the cost for each I/O per second is comparable. Compared to traditional high-end storage arrays, low-cost storage arrays have excellent data throughput and superior price for each gigabyte.
Low-cost storage is most successfully deployed for databases with certain types of performance and availability requirements. Low-cost storage arrays, low-cost storage networks, and Oracle Database 10 g can in combination create a low-cost storage grid with excellent performance and availability.
Along with understanding the database performance requirements, the performance capabilities of a storage array must be evaluated. The necessary statistics can be derived from Automatic Workload Repository (AWR) reports or gathered from the GV$SYSSTAT view. Extract statistics during your target workloads by getting the beginning and end statistical snapshots. 2.1.1 Evaluate Database Performance Requirements and Storage Performance CapabilitiesĬharacterize your database performance requirements using different application workloads.
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