Expand Configuration and Management Manual (G06.24+)

Tuning
Expand Configuration and Management Manual—523347-008
20-22
Summary of Tuning Strategies
Summary of Tuning Strategies
Table 20-4 summarizes the strategies that you can use to achieve your tuning goals.
Measuring and Mapping an Expand Network
Effective network tuning must begin with an accurate picture of the network and its
significant traffic. All networks are fully defined topologically by their nodes and links.
Network traffic is fully defined by the intensity of the traffic, the service times of the
working components, and the capacities of passive resources such as buffers and
queues. These parameters can all be measured by HP utilities.
Because it is not always feasible to define every network fully, your first task is to
create a working definition of a subnetwork adequate to serve tuning goals. HP
provides several tools for building this model:
Table 20-4. Summary of Tuning Strategies
Goal Strategies
To optimize resource use
and minimize cost
Use the multipacket frame feature for OLTP applications and
the variable packet size feature for bulk data transfers. Both
features can be used on the same path.
Minimize passthrough traffic to save time and capital costs
while maintaining fault-tolerance.
Use single-line paths where possible.
To maximize throughput Use the multipacket frame feature for OLTP applications and
the variable packet size feature for bulk data transfers. Both
features can be used on the same path.
Provide adequate communications bandwidth to meet the path
demand.
Configure Expand line-handler processes to use data
compression (COMPRESS_ON modifier).
Install single high-speed lines rather than multiple low-speed
lines.
To minimize delay Use direct connections between nodes to avoid passthrough
and its associated delays.
Do not use X.25 or store-and-forward type switches.
Use two or more times the communications line capacity than
is required to minimize queuing delays.
Configure Expand line-handler processes in lightly loaded
processors.
Configure Expand-over-NAM line-handler processes in the
same processor if that processor has sufficient capacity.
Avoid satellite connections in multiple hop topologies. (Use
satellite connections where the network has delays.)