NetBackup™ Backup Planning and Performance Tuning Guide
- NetBackup capacity planning
- Primary server configuration guidelines
- Media server configuration guidelines
- NetBackup hardware design and tuning considerations
- About NetBackup Media Server Deduplication (MSDP)
- MSDP tuning considerations
- MSDP sizing considerations
- Accelerator performance considerations
- Media configuration guidelines
- How to identify performance bottlenecks
- Best practices
- Best practices: NetBackup AdvancedDisk
- Best practices: NetBackup tape drive cleaning
- Best practices: Universal shares
- NetBackup for VMware sizing and best practices
- Best practices: Storage lifecycle policies (SLPs)
- Measuring Performance
- Table of NetBackup All Log Entries report
- Evaluating system components
- Tuning the NetBackup data transfer path
- NetBackup network performance in the data transfer path
- NetBackup server performance in the data transfer path
- About shared memory (number and size of data buffers)
- About the communication between NetBackup client and media server
- Effect of fragment size on NetBackup restores
- Other NetBackup restore performance issues
- About shared memory (number and size of data buffers)
- Tuning other NetBackup components
- How to improve NetBackup resource allocation
- How to improve FlashBackup performance
- Tuning disk I/O performance
Recommended shared memory settings
Note:
for the default number of shared data buffers for various NetBackup operations.
The SIZE_DATA_BUFFERS setting for backup to tape is typically increased to 256 KB and NUMBER_DATA_BUFFERS is increased to 16. To configure NetBackup to use 16 x 256-KB data buffers, specify 262144 (256 x 1024) in SIZE_DATA_BUFFERS and 16 in NUMBER_DATA_BUFFERS.
Note that an increase in the size and number of the data buffers uses up more shared memory, which is a limited system resource. The total amount of shared memory that is used for each tape drive is:
Shared memory = (number_data_buffers * size_data_buffers) * number_tape_drives * max_multiplexing_setting
For two tape drives, each with a multiplexing setting of 4 and with 16 buffers of 256KB, the total shared memory usage would be:
(16 * 262144) * 2 * 4 = 32768 KB (32 MB)
If large amounts of memory are to be allocated, the kernel may require additional tuning to provide enough shared memory for NetBackup.
Make changes carefully, monitoring for performance changes with each modification. For example, an increase in the tape buffer size can cause some backups to run slower. Also, there have been cases with restore issues. After any changes, be sure to include restores as part of your validation testing.
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