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File-by-file backup or archive methods provide the best restore performance if you only need to restore
individual files. However, if the average file size is small, file-by-file methods will significantly reduce
performance.
Disk image, flash, or sequential backup methods provide the fastest performance because they back up
an entire disk, partition, or LUN, which minimizes disk seeking. The disadvantage is that backup and
restore operations work on an entire disk, partition, or LUN. You might not be able to back up a subset of
files or restore a single file. If you can restore a single file, the restore process will be slow.
Database backup performance will vary based on the use model. To improve performance when backing
up data from a database:
•
Use specific backup agents for the database.
•
Use the latest versions of the databases.
•
Do not back up individual mailboxes.
•
Do not back up specific records or do a record-by-record backup.
•
Do not back up when the database is in heavy use.
Connection from the archive/backup host server to the library
For the best performance, the connection from the host server to the library must have enough bandwidth
to provide enough data to keep the tape drive streaming. Current LTO tape drives take advantage of
some of the fastest interfaces available so the type of interface used to connect the library to the host
server is not likely to be the cause of a performance issue. However, issues with cables and connectors
can limit performance.
Verify that the system is using cables that are listed in the QuickSpecs, are in good condition, and do not
exceed recommended cable lengths.
Data cartridges
The type and condition of the data cartridges also affect backup performance. For best performance, use
Hewlett Packard Enterprise cartridges that are the same LTO generation as the tape drives. If you
suspect a performance issue related to data cartridges, use the L&TT media assessment test to evaluate
the condition of the data cartridges.
Tape drive read or write performance seems slow
Symptom
Tape drive read or write is slower than expected.
Cause
If the tape drive is not properly secured to the chassis or the library is not properly secured to the rack,
vibration may cause slow read or write performance. Vibration could come from the cooling fan or
external sources.
Action
1. Ensure that the tape drives are securely tightened to the chassis.
Use a torque driver to tighten the thumbscrews on all the tape drives to 6 inch pounds or 0.68 N m.
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Connection from the archive/backup host server to the library
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