Configuring buffer size for backups
The read or write buffer size for object stores influence the performance of NetBackup in the cloud object stores.
Note:
The configurations described in this section are not required if your backup host is NetBackup version 11.0 or higher, and your policy does not have Dynamic multi-streaming enabled. For policies with Dynamic multi-streaming, see the section Configuring a temporary staging location.
By default, NetBackup creates buffers of 4 MB. You can use this default buffer size, if most of the objects in your buckets/containers are less than 4 MB. If your buckets/containers have a large number of objects greater than 4 MB then you can increase the buffer size up to 64 MB.
To configure buffer size:
- Open the
/usr/openv/netbackup/bp.conffile on the backup host.You can identify the backup host from the corresponding policy under the Cloud objects tab.
- Enter a value for this parameter in MB: COS_SHM_BUFFER_SIZE =
For example:COS_SHM_BUFFER_SIZE = 16
By default, NetBackup creates seven buffers for each read or write operation. Depending on the availability of memory on the backup host, you can set the number of buffers to 4 to 16 buffers for each stream. Increasing the number of buffers results in faster backups, but the memory usage on the backup host may increase.
To configure the number of buffers:
- Open the
/usr/openv/netbackup/bp.conffile on the backup host. - Enter a value for this parameter in MB: COS_NO_SHM_BUFFER =
For example: COS_NO_SHM_BUFFER = 12
Note that these settings are applied to all backup jobs that use that backup host.