Databases Reference
In-Depth Information
We learned that there are many cache instances in Liferay Portal. It is not possible
to monitor every instance during load tests. Hence, cache monitoring is done based
on specific performance issues. Depending on the most used functionalities of the
Portal, cache instances should be identified and monitoring those cache instances
should be done during a load test.
During a load test, if it is found that the value of the
CacheMisses
attribute is very
high, it indicates that the cache is undersized. In that case, the size of the cache
should be increased.
Apache web server - monitoring and tuning
In our reference architecture, we have used an Apache web server in front of Liferay
Portal servers. During a load test, we need to monitor the following resources of the
Apache web server.
• CPU and memory
• Worker threads
There are many tools available in the market to monitor CPU and memory
consumption of the Apache web server. On a Linux- or Unix-based server, we can
simply use the TOP command to monitor CPU and memory consumption. With
this option, it will be difficult to monitor resource usage over time. For this kind of
monitoring, any SNMP-based monitoring tool can be used. Nagios is one of the most
powerful open source monitoring tools. The Apache web server can be configured
with Nagios to monitor CPU and memory consumption. With the use of Nagios, we
can monitor worker threads as well.
The Apache web server also comes up with a simple monitoring module called
mod_status
. It can be used to monitor worker threads. The following are the
steps to enable this tool:
1.
Locate the
httpd.conf
file in the
<APACHE_HOME>/conf
directory on the
Apache web server and add the following configuration into it:
LoadModule status_module modules/mod_status.so
ExtendedStatus On
<location /server-status>
SetHandler server-status
Order allow,deny
Allow from all
</location>
2.
Restar
t the Apache web server.
3.
