FW 05.01.00 and SW 07.01.00 HP StorageWorks SAN High Availability Planning Guide (AA-RS2DC-TE, June 2003)

Planning Considerations for Fibre Channel Topologies
102 SAN High Availability Planning Guide
Figure 43: Device fan-out ratio
Performance Tuning
When designing or tuning a fabric for performance, it is critical to understand
application I/O characteristics so that:
■ Device output in Gbps does not oversubscribe ISLs, leading to fabric
congestion.
■ Device output in IOPS does not result in a connectivity scheme that exceeds
fan-out ratios, leading to port congestion.
T
M
T
M
Interswitch Link
Fabric Connection
1,000 IOPS
1,000 IOPS
1,000 IOPS
1,000 IOPS
1,000 IOPS
1,000 IOPS
10,000 IOPS
1,000 IOPS
1,000 IOPS
1,000 IOPS
1,000 IOPS
Device Fan-Out Ratio: 10 to 1