About NetBackup performance and the hardware hierarchy
The critical factors in NetBackup performance are not software-based. The critical factors are hardware selection and configuration. Hardware has roughly four times the weight that software has in determining performance.
Figure: Performance hierarchy diagram shows the key hardware elements that affect performance, and the interconnections (levels) between them. The figure shows two disk arrays and a single non-disk device (tape, Ethernet connections, and so forth).
Performance hierarchy levels are described in later sections of this chapter.
In general, all data that goes to or comes from disk or SSD must pass through host memory.
Figure: Data stream in NetBackup media server to arrays includes a dashed line that shows the path that the data takes through a media server.
The data moves up through an Ethernet NIC or Fibre Channel HBA on the client, to the Ethernet NIC or Fibre Channel HBA on the media server, acting as a target in this example, located in the rightmost PCIe slot. The data then moves directly into the Processor that is assigned to the PCIe slot and then to host memory. NetBackup then writes the new data to the appropriate location on the storage devices, via the PCIe NIC or HBA that interface with the RAID controllers. The data resides in the memory while NetBackup ascertains status: if it has been seen before or it is new and needs to be deduplicated. Efficiency of the PCIe lanes as components of the CPU drastically increases speed and lowers latency when compared to previous processors that required a companion chip to act as a bridge to the CPU.