HP StorageWorks XP Remote Web Console Software - Manual (Page 13)

Performance Control XP user guide 13
For detailed information about monitoring traffic, see ” Setting the priority of ports on disk arrays ” on
page 22 and ” Measuring traffic between host bus adapters and ports for many-to-many connections ”
on page 22.
Figure 3 Traffic at ports on network A
3. Set an upper limit to traffic at non-prioritized ports. To maintain I/O rates at prioritized ports, set upper
limit values to the I/O rate for non-prioritized ports.
When you first set an upper limit, HP recommends an upper limit of approximately 90 percent of peak
traffic. In network A, the peak I/O rate for the non-prioritized port (2A) is 200 IO/s, so the
recommended upper limit is 180 IO/s.
For detailed information, see ”
Setting upper limit values for traffic at non-prioritized ports or WWNs ”
on page 23.
4. Check the result of applying upper limit values. After applying upper limit values, measure traffic at
ports by viewing traffic statistics for prioritized ports 1A and 1C to check whether the host performance
has improved to a desirable level.
In network A, if the desirable I/O rate (400 IO/s for ports 1A and 1C) has not been achieved, change
the upper limit for port 2A to a lower value and apply the new upper limit to the disk array. In network
A, if the upper limit is set to 180 IO/s but the I/O rate for 1A and 1C is still below 400 IO/s, reduce
the upper limit until the I/O rate reaches 400 IO/s.
5. If necessary, apply a threshold. To use threshold control, set threshold values in the Port tab in the
Performance Control pane. You can set threshold values in either of the following ways:
• Set one threshold for each prioritized port.
In network A, if you set a threshold of 200 IO/s for port 1A and 100 IO/s for port 1C, the upper
limit on the non-prioritized port (2A) is disabled when either of the following conditions is met:
• I/O rate for port 1A is 200 IO/s or lower
• I/O rate for port 1C is 100 IO/s or lower
• Set only one threshold for the entire disk array.
In network A, if you set a threshold of 500 IO/s for the disk array, the upper limit on the
non-prioritized port (2A) is disabled when the sum of the I/O rates for all prioritized ports (1A and
1C) falls below 500 IO/s.
For detailed information, see ” Setting thresholds ” on page 24.
Procedure for many-to-many connections between HBAs and ports
Figure 4 shows an example of a network where a production server and development server are
connected to the disk array. (Henceforth, this network is referred to as network B.) The host bus adapter