NetBackup™ Backup Planning and Performance Tuning Guide
- NetBackup capacity planning
- Primary server configuration guidelines
- Size guidance for the NetBackup primary server and domain
- Factors that limit job scheduling
- More than one backup job per second
- Stagger the submission of jobs for better load distribution
- NetBackup job delays
- Selection of storage units: performance considerations
- About file system capacity and NetBackup performance
- About the primary server NetBackup catalog
- Guidelines for managing the primary server NetBackup catalog
- Adjusting the batch size for sending metadata to the NetBackup catalog
- Methods for managing the catalog size
- Performance guidelines for NetBackup policies
- Legacy error log fields
- Media server configuration guidelines
- NetBackup hardware design and tuning considerations
- About NetBackup Media Server Deduplication (MSDP)
- Data segmentation
- Fingerprint lookup for deduplication
- Predictive and sampling cache scheme
- Data store
- Space reclamation
- System resource usage and tuning considerations
- Memory considerations
- I/O considerations
- Network considerations
- CPU considerations
- OS tuning considerations
- MSDP tuning considerations
- MSDP sizing considerations
- Cloud tier sizing and performance
- Accelerator performance considerations
- Media configuration guidelines
- About dedicated versus shared backup environments
- Suggestions for NetBackup media pools
- Disk versus tape: performance considerations
- NetBackup media not available
- About the threshold for media errors
- Adjusting the media_error_threshold
- About tape I/O error handling
- About NetBackup media manager tape drive selection
- How to identify performance bottlenecks
- Best practices
- Best practices: NetBackup SAN Client
- Best practices: NetBackup AdvancedDisk
- Best practices: Disk pool configuration - setting concurrent jobs and maximum I/O streams
- Best practices: About disk staging and NetBackup performance
- Best practices: Supported tape drive technologies for NetBackup
- Best practices: NetBackup tape drive cleaning
- Best practices: NetBackup data recovery methods
- Best practices: Suggestions for disaster recovery planning
- Best practices: NetBackup naming conventions
- Best practices: NetBackup duplication
- Best practices: NetBackup deduplication
- Best practices: Universal shares
- NetBackup for VMware sizing and best practices
- Best practices: Storage lifecycle policies (SLPs)
- Best practices: NetBackup NAS-Data-Protection (D-NAS)
- Best practices: NetBackup for Nutanix AHV
- Best practices: NetBackup Sybase database
- Best practices: Avoiding media server resource bottlenecks with Oracle VLDB backups
- Best practices: Avoiding media server resource bottlenecks with MSDPLB+ prefix policy
- Best practices: Cloud deployment considerations
- Measuring Performance
- Measuring NetBackup performance: overview
- How to control system variables for consistent testing conditions
- Running a performance test without interference from other jobs
- About evaluating NetBackup performance
- Evaluating NetBackup performance through the Activity Monitor
- Evaluating NetBackup performance through the All Log Entries report
- Table of NetBackup All Log Entries report
- Evaluating system components
- About measuring performance independent of tape or disk output
- Measuring performance with bpbkar
- Bypassing disk performance with the SKIP_DISK_WRITES touch file
- Measuring performance with the GEN_DATA directive (Linux/UNIX)
- Monitoring Linux/UNIX CPU load
- Monitoring Linux/UNIX memory use
- Monitoring Linux/UNIX disk load
- Monitoring Linux/UNIX network traffic
- Monitoring Linux/Unix system resource usage with dstat
- About the Windows Performance Monitor
- Monitoring Windows CPU load
- Monitoring Windows memory use
- Monitoring Windows disk load
- Increasing disk performance
- Tuning the NetBackup data transfer path
- About the NetBackup data transfer path
- About tuning the data transfer path
- Tuning suggestions for the NetBackup data transfer path
- NetBackup client performance in the 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)
- Default number of shared data buffers
- Default size of shared data buffers
- Amount of shared memory required by NetBackup
- How to change the number of shared data buffers
- Notes on number data buffers files
- How to change the size of shared data buffers
- Notes on size data buffer files
- Size values for shared data buffers
- Note on shared memory and NetBackup for NDMP
- Recommended shared memory settings
- Recommended number of data buffers for SAN Client and FT media server
- Testing changes made to shared memory
- About NetBackup wait and delay counters
- Changing parent and child delay values for NetBackup
- About the communication between NetBackup client and media server
- Processes used in NetBackup client-server communication
- Roles of processes during backup and restore
- Finding wait and delay counter values
- Note on log file creation
- About tunable parameters reported in the bptm log
- Example of using wait and delay counter values
- Issues uncovered by wait and delay counter values
- Estimating the effect of multiple copies on backup performance
- Effect of fragment size on NetBackup restores
- Other NetBackup restore performance issues
- About shared memory (number and size of data buffers)
- NetBackup storage device performance in the data transfer path
- Tuning other NetBackup components
- When to use multiplexing and multiple data streams
- Effects of multiplexing and multistreaming on backup and restore
- How to improve NetBackup resource allocation
- Encryption and NetBackup performance
- Compression and NetBackup performance
- How to enable NetBackup compression
- Effect of encryption plus compression on NetBackup performance
- Information on NetBackup Java performance improvements
- Information on NetBackup Vault
- Fast recovery with Bare Metal Restore
- How to improve performance when backing up many small files
- How to improve FlashBackup performance
- Veritas NetBackup OpsCenter
- Tuning disk I/O performance
Disk versus tape: performance considerations
Disk is now a common backup medium. Backup data on disk generally provides faster restores.
Tuning disk-based storage for performance is similar to tuning tape-based storage. The optimal buffer settings for a site can vary according to its configuration. It takes thorough testing to determine these settings.
Disk-based storage can be useful if you have a lot of incremental backups and the percentage of data change is small. If the volume of data in incremental copies is insufficient to ensure efficient writing to tape, consider disk storage. After writing the data to disk, you can use staging or storage lifecycle policies to copy batches of the images to tape. This arrangement can produce faster backups and prevent wear and tear on your tape drives.
Consider the following factors when backing up a data set to disk or tape:
Short or long retention period
Disk is well suited for short retention periods; tape is better suited for longer retention periods.
Intermediate (staging) or long-term storage
Disk is suited for staging; tape for long-term storage.
Disk is better suited to low volume incremental backups.
Synthetic backups
Synthetic full backups are faster when incremental backups are stored on disk.
Restore from disk is usually faster than from tape.
Multistreamed restore
Must a restore of the data be multistreamed from tape? If so, do not stage the multistreamed backup to disk before writing it to tape.
Speed of the backups
If client backups are too slow to keep the tape in motion, send the backups to disk. Later, staging or lifecycle policies can move the backup images to tape.
Size of the backups
If the backups are too small to keep the tape in motion, send the backups to disk. Small backups may include incrementals and frequent backups of small database log files. Staging or lifecycle policies can later move the backup images to tape.
The following are some benefits of backing up to disk rather than tape:
Backups to disk do not need to be multiplexed. Multiplexing is important with tape because it creates a steady flow of data which keeps the tape in motion efficiently (tape streaming). However, multiplexing to tape slows down a subsequent restore.
More information is available on tape streaming.
See NetBackup storage device performance in the data transfer path.
Faster access to data
Most tape drives have a "time to data" of close to two minutes. Time is required to move the tape from its slot, load it into the drive, and seek to an appropriate place on the tape. Disk has an effective time to data of 0 seconds. Restoring a large file system from 30 different tapes can add almost two hours to the restore: a two-minute delay per tape for load and seek, and a possible two-minute delay per tape for rewind and unload.
With tape-based systems, full backups must be done regularly because of the "time to data" issue. If full backups are not done regularly, a restore may require too many tapes from incremental backups. As a result, the time to restore increases, as does the chance that a single tape may cause the restore to fail.