HP Data Protector Software Performance White Paper

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Backup performance
Backup performance will always be limited by one or more bottlenecks in the system, of which
the tape drive is just one part.
The flow of data throughout the system must be fast enough to provide the tape drive with data
at its desired rates. High-speed tape drives, such as the HP StorageWorks Ultrium 960 tape
drive, are so fast that making them the bottleneck can be very challenging.
All components must be considered and analyzed for getting the best backup performance.
Standard configurations with default values are mostly not sufficient. In enterprise environments,
performance estimations are very difficult to provide without benchmarks.
Restore performance
Many backup environments are tuned for backup performance because frequent backups
require most resources. Large restores are less common and so runtimes are less predictable.
Backup runtimes cannot be used for calculating exact restore runtimes. Therefore, runtimes can
only be proved by restore tests.
Backup and restore data path
The limiting component of the overall backup and restore performance is the slowest component
in the backup environment. For example, a fast tape drive combined with an overloaded server
results in poor performance. Similarly, a fast tape drive on a slow network also results in poor
performance.
The backup and restore performance depends on the complete data transfer path.
Figure 6 shows that the backup path usually starts at the data on the disk and ends with a copy
on tape. The restore path is the other way round. Ideally, the tape drive should be the limiting
factor in the data path. All other components should process data faster than the tape drive so
the tape drive has never to wait for data.
Figure 6. Backup and restore data path
Manager server (Data Protector Cell Manager)
The Cell Manager should be sized according to its installation requirements.
Note: Additional applications or backups on the Cell Manager will increase the installation
requirements. Please check carefully any application installation requirements. In larger backup
environments, it is not recommended to share this server with other applications or to use it as a
backup server.
The server should be clustered for having no Single Point of Failure (SPOF) in the backup
environment. The network connections to each client are essential and should be protected
against single link failures.
Backup and application server (Data Protector Client System)
Backup and application servers should be sized according to the installation requirements.