IBM DS6000 Series manual Fibre Channel device adapter, New four-port host adapters

This just outlines the physical structure. A virtualization approach built on top of the high performance architecture contributes even further to enhanced performance. For details see Chapter 4, “Virtualization concepts” on page 65.

11.3.2 Fibre Channel device adapter

The DS6000 still relies on eight DDMs to form a RAID-5 or a RAID-10 array. With the virtualization approach and the concept of extents, the DAs are mapping the virtualization level over the disk subsystem back end. For more details on the disk subsystem virtualization refer to Chapter 4, “Virtualization concepts” on page 65.

To host servers
Adapter		Adapter			Controller
				Host adapter
					Card 1
				chipset
Processor	Memory	Processor	server	Power PC
					Processor
			Storage	chipset	memory
Adapter		Adapter			Volatile
				Device adapter
					Persistent
				chipset
				2 Gbps Fibre Channel ports

Figure 11-4 Fibre Channel device adapter with 2 Gbps ports

The new RAID device adapter chipset connects to four 2 Gbps Fibre Channel ports and high function, high performance ASICs. Each port provides up to five times the throughput of a previous SSA-based DA port.

Note that each DA chipset performs the RAID logic and frees up the processors from this task. The actual throughput and performance of a DA is not only determined by the 2 Gbps ports and used hardware, but also by the firmware efficiency.

11.3.3 New four-port host adapters

Before looking into the server complex we briefly review the new host adapters and their enhancements to address performance. Figure 11-5 on page 227 depicts the new host adapters. These adapters are designed to hold four Fibre Channel ports, which can be configured to support either FCP or FICON.

Each port continues the tradition of providing industry-leading throughput and I/O rates for FICON and FCP.

Note that a FICON channel can address up to 16,384 devices through a FICON port. The DS6000 series can hold up to 8,192 devices. So all devices within a DS6000 series can be reached through a FICON port. Whether this is desirable is a different question and is discussed further in “Configuration recommendations for z/OS” on page 237.

226DS6000 Series: Concepts and Architecture