HPjmeter 4.3 User's Guide

Node agent
On HP-UX systems, the node agent may occasionally leave files in /var/opt/hpjmeter/fifos,
with names ending with *fifo. These files are used for node agent communication, and you
should not remove them while a node agent or JVM agent is active. You can delete these files
when the node agent is not running if they begin to accumulate.
• On HP-UX you may sometimes not be able to restart the node agent with the same port. If you
stopped the node agent and then tried to run it again, you may see the following:
Can't use port port_number. Try using the -port option to select a port from 9505 to 9515.
To work around the problem, restart the node agent using a different port number.
If the problem with the un-terminated connections persists, you can reduce the frequency by
using this command as root:
$ ndd -set /dev/tcp tcp_fin_wait_2_timeout
300000
This sets the timeout in milliseconds for the leftover connections. The example sets this timeout
to 5 minutes (300000 milliseconds). After about five minutes, you should be able to restart
the server using the same port number as before.
• You can set a log level on the node agent, which lets you collect varying amounts of information
about the console and node agent. To set the log level, use this command to manually start
a new node agent:
$ JMETER_HOME/bin/nodeagent -logging=level_of_detail
Available log levels:
◦ FINEST (most impact on performance)
◦ FINER
◦ FINE
◦ CONFIG
◦ INFO
◦ WARNING (default setting)
◦ SEVERE (least impact on performance)
For more information about the node agent, see Managing Node Agents (page 47).
Zero Preparation Profiling
We have suggested that you use -usr2 to start and stop zero preparation profiling from the
command line. Because some applications use this same signal, you may want to disable the ability
to do zero preparation profiling altogether to avoid interfering with your application. To disable
zero preparation profiling, use -xeprof:off
Unexpected Behavior in Visualizers
For best results, update the HPjmeter node agent on your server(s) when you update the console.
This allows you to take advantage of new metrics or improved support for newer JDKs/JREs.
Node agent 221