HP BL536A, Руководство пользователя и обслуживания

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are concerned about viruses and backup performance, perform a virus scan before starting the
backup, and shut down the anti-virus software while the backup is running.
Novell
You might need to tweak some Novell operating system parameters to achieve good backup
performance.
•
The MAXIMUM PACKET RECEIVE BUFFERS and MINIMUM PACKET RECEIVE BUFFERS
parameters may need to be increased (if currently maxed out, try setting the MINIMUM to the
current MAXIMUM and then double the value for the MAXIMUM on the backup server and
any remote servers that are backed up).
•
The MAXIMUM DIRECTORY CACHE BUFFERS and MINIMUM DIRECTORY CACHE BUFFERS
parameters may need to be increased (if currently maxed out, try setting the MINIMUM to the
current MAXIMUM and then double the value for the MAXIMUM on the backup server and
any remote servers that are backed up.)
•
Set TCP DELAYED ACKNOWLEDGEMENTS to OFF.
•
Since Novell volumes may be compressed, hardware compression may lower the performance
and capacity. If the volumes are compressed, make sure that the backup software does not
uncompress the data on read and has hardware and software compression disabled.
NOTE: Disabling the hardware compression should not be necessary on Ultrium drives as
they sense the compression ratios and can automatically adjust if they receive non-compressable
data.
•
Stop as many programs as possible while a backup or restore is in progress. Be especially
aware of monitoring applications, such as anti-virus software, which check every file that is
read. If you are concerned about viruses and backup performance, perform a virus scan
before starting the backup, and shut down the anti-virus software while the backup is running.
Backup server
The backup server must have enough RAM and processor power to transfer the files from the disk
to the tape drive. See
Table 30 (page 101) for the minimum RAM and CPU speed needed for each
tape drive. In some cases, a multi-processor server may be required.
NOTE: Processor speed numbers as based on Intel x86 type processors. Use the equivalent on
a RISC or other type of processor.
Table 30 Backup server requirements
Processor power/drive Minimum RAM/drive Tape drive
1 GHz 512 MB LTO-2
2 GHz 1 GB LTO-3, LTO-4
4 GHz 2 GB LTO-5
In addition to having enough RAM and processing power, ensure that the PCIe bus is at least 64
bit, has a speed of 66 MHz or better, and is not overloaded by too many high-bandwidth cards.
PCIe is preferred.
Backup type
Each type of backup has its own impact on performance, depending on how well it can keep data
streaming to the tape drive.
Performance problems 101