AIX 5L Problem Determination - IBM Redbooks

The retrans column displays the number of times requests were retransmitted
due to a timeout in waiting for a response. This situation is related to dropped
UDP packets. If the retrans number consistently exceeds five percent of the
total calls in column one, it indicates a problem with the server keeping up
with demand.
When going into more detailed output, the netpmon command, using a trace
facility, is useful.
10.4.3 The netpmon command
The netpmon command monitors a trace of system events and reports on network
activity and performance during the monitored interval. By default, the netpmon
command runs in the background while one or more application programs or
system commands are being executed and monitored. The netpmon command
automatically starts and monitors a trace of network-related system events in
real time.
10.5 Workload Manager (WLM)
WLM is designed to give system administrators more control over how the
scheduler and the virtual memory manager (VMM) allocate resources to
processes. This can be used to prevent different classes of jobs from interfering
with each other and to allocate resources based on the requirements of different
groups of users.
With WLM, you can create different classes of service for jobs, as well as specify
attributes for those classes. These attributes specify minimum and maximum
amounts of CPU, physical memory, and disk I/O throughput to be allocated to a
class. WLM then assigns jobs automatically to classes using class assignment
rules provided by a system administrator. These assignment rules are based on
the values of a set of attributes for a process. Either the system administrator or
a privileged user can also manually assign jobs to classes, overriding the
automatic assignment.
Class definitions, class attributes, the shares and limits, and the automatic class
assignment rules, can be entered using Web-based System Manager, SMIT, or
the WLM command-line interface. These definitions and rules are kept in plain
text files that can also be created or modified using a text editor.
The system administrator can specify the properties for the WLM subsystem by
using either the Web-based System Manager graphical user interface, SMIT
ASCII-oriented interface, the WLM command line interface, or by creating flat
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