Basic Tuning Suggestions to Maximize the Backup Performance
The following section provides several parameters to improve your backup system performance and avoid bottlenecks.
On a Subclient
Use Multiple Data Readers
- Data Readers
Data Readers determines the number of parallel read operations while the data is backed up. Configuring multiple data readers per subclient on disk arrays can improve the backup performance of clients.
Modify the number of data readers on a subclient to twice the number of tape drives.
See Setting the Data Readers for File System Agents for instructions about how to modify the value.
- Allow multiple data readers within a drive or mount point
Configure multiple data readers for a disk array that contains several physical drives that are logically addressed as a single drive. This allows you to take advantage of the fast read access from the array.
See Setting the Data Readers for File System Agents for instructions about how to enable this option.
- Network Agents establish data pipes to transfer data from the client to the MediaAgent. Therefore, increasing the number of Network Agents increases the data transfer throughput from the client.
Depending upon your environment, change the Network Agents value to 2.
See Network Agents for instructions about modifying the value for network agents.
On a Storage Policy
- Device Streams
Device Streams are logical channels that connect client data to the media where data that is secured by backup operations are stored.
On Storage Policy, the number of device streams that is configured must be equal to the number of drives or writers of all libraries that are defined in the storage policy copy.
See Setting the Device Streams on a Storage Policy for instructions about how to modify the value.
- Incremental Storage Policy
Enable Incremental Storage Policy on Storage Policy properties. Once this option is enabled, the selected storage policy is used to perform incremental and differential backups.
On a Storage Policy Copy
Enabling multiplexing allows multiple backups to run in parallel to a single tape drive. This results in better usage of the tape drives, especially when the backups are from slower clients. This helps in better overall throughput and reduction in the backup window.
For LAN backups, make sure that the network between the clients and MediaAgent is capable of supporting multiple simultaneous backups.
- Typical multiplexing factors are set between 2 and 5 on 100BaseT networks.
- Typical multiplexing factors are set between 5 and 8 on 1000BaseT networks.
- Multiplexing Factor
You can determine the multiplexing factor by analyzing the network configuration and the required disk throughput. For better performance of backups, set the multiplexing factor to twice the number of tape drives.
See Configuring Data Multiplexing for instructions.
- Use Device Streams rather than multiplexing
Enable Use Device Streams rather than multiplexing to copy the data streams on each available drives first and then on used drives.
On a CommCell
- Increase the Chunk Size
Setting the chunk size higher (for example, 16384 MB for a Linux file system) increases throughput.
Last modified: 8/10/2018 3:28:29 PM