AEM Tools for Monitoring and Analyzing Performance

The following gives a short overview of some of the tools available for monitoring and analyzing performance.

Some of these will be dependent on your operating system.

Tool	Used to analyze...	Usage / More information...
request.log	Response times and concurrency.	Inter request.log.preting the
truss/strace	Page Loads	Unix/Linux commands to trace system calls and signals. Increase the log level to INFO. Analyze the number of page loads per request, which pages, etc.
Thread dumps	Observe JVM threads. Identify contentions, locks and long-runners.	Dependent on the operating system: - Unix/Linux: kill -QUIT <pid> - Windows (console mode): Ctrl-Break Analysis tools are also available, such as TDA.
Heap Dumps	Out of Memory issues that cause slow performance.	Add the:     -XX:+HeapDumpOnOutOfMemoryError option to the java call to CQ. See the Troubleshooting Guide for Java SE 6 with HotSpot VM.
System calls	Identify timing issues.	Calls to System.currentTimeMillis() or com.day.util.Timing are used to generate timestamps from your code, or via HTML-comments. Note: These should be implemented so that they can be activated / deactivated as required; when a system is running smoothly the overhead of collecting statistics will not be needed.
Apache Bench	Identify memory leaks, selectively analyze response time.	basic usage is: ab -k -n <requests> -c <concurrency> <url> See Apache Bench and the ab man page for full details.
Search Analysis		Execute search queries offline, identify response time of query, test and confirm result set.
JMeter	Load and functional tests.	http://jakarta.apache.org/jmeter/
JProfiler	In-depth CPU and memory profiling.	http://www.ej-technologies.com/
JConsole	Observe JVM metrics and threads.	Usage: jconsole See jconsole and Monitoring Performance using JConsole. Note: With JDK 1.6, JConsole is extensible with plug-ins; for example, Top or TDA (Thread Dump Analyzer).
Java VisualVM	Observe JVM metrics, threads, memory and profiling.	Usage: jvisualvm or visualvm See jvisualvm, visualvm and Monitoring Performance using (J)VisualVM. Note: With JDK 1.6, VisualVM is extensible with plug-ins.
truss/strace, lsof	In depth kernel call and process analysis (Unix).	Unix/Linux commands.
Timing Statistics	See timing statistics for page rendering.	To see timing statistics for page rendering you can use Ctrl-Shift-U together with ?debugClientLibs=true set in the URL.
CPU and memory profiling tool	Used when analyzing slow requests during development.	For example, YourKit.
Information Collection	The ongoing state of your installation.	Knowing as much as possible about your installation can also help you track down what might have caused a change in performance, and whether these changes are justified. These metrics need to be collected at regular intervals so you can easily see significant changes.