Traffic Between Hbas And Storage System Ports; Performance Of High-Priority Hosts - Hitachi MK-96RD617-08 User Manual

Traffic between HBAs and Storage System Ports

Host bus adapters (HBAs) are adapters contained in hosts. HBAs, which serve
as ports on hosts, are connected to ports on the storage system.
If Server Priority Manager is enabled, Performance Monitor lets you view
statistics about traffic between HBAs and storage system ports. The traffic
statistics reveals the number of I/O requests that have been made from hosts
and also reveals the size of data transferred between hosts and storage
system ports. For details on how to view traffic statistics about HBAs, see
Viewing HBA Information.
Statistics can be stored for time periods of 8 hours or up to 15 days, and
changes depending on the collecting interval specified. Statistics that have
expired are erased from the storage system. For details on the storing period
of statistics, see Understanding Statistical Storage Ranges.
Overview of Server Priority Manager
When Server Priority Manager is used, I/O operations from hosts requiring
high performance are given higher priority over I/O operations from other
hosts.

Performance of High-Priority Hosts

In an SAN (storage area network) environment, the storage system is usually
connected with a lot of host servers. Some types of the host servers often
require high performance but others might not require as high performance.
For example, production servers usually require high performance. Production
servers, which include database servers and application servers, are used to
perform daily tasks of business organizations. If production servers suffer
lowered performance, productivity in business activities is likely to be
damaged. For this reason, the system administrator needs to maintain
performance of production servers at a higher level.
Computer systems in business organizations often include development
servers as well as production servers. Development servers are used for
developing, testing and debugging business applications. If development
servers suffer lowered performance, it would bring undesirable results to
developers. However, a decline in development server performance would not
bring as much negative impact to the entire organization as a decline in
production server performance. In this sense, production servers should be
given higher priority over development servers.
Hitachi Universal Storage Platform V/VM Hitachi Performance Manager User's Guide
About Performance Manager Options 2-13