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Monitor your Web server in real time, part 3

We wrap up our three-part series on how to monitor realtime events with Java with some additions to the Percollator applet

By Rinaldo S. Di Giorgio, JavaWorld.com, 12/01/96

This is the last and final installment in the Percollator series. The Percollator applet has been developed over several columns in JavaWorld. The data for Percollator is generated by Percollator.se described in the companion article. In this article we will discuss the following additions to Percollator:

• Addition of a Gantt-like chart that displays the status of the rules as reported by SE tool -- a tool for monitoring Solaris Operating Systems with rule based metrics, recently enhanced to support Internet metrics. Here is a snapshot that shows what it looks like. (We provide this and other screen shots in GIF format for readers who do not have Java VM ability).
• • Performance measurement of the above using the new Guava compiler
  • Improved appearance of the User Interface and new summary with nine graphs. Here is a snapshot.
• Integrating persistence into the Percollator applet.
• • Example background process that takes rule data and saves it in a persistent database.
  • Using a calendar-like interface to navigate. (Here is a snapshot.)
• A collection of status indicators for your desktop. (Here is a snapshot.)
• Update on VRML  representation of the data.

Use the Percollator applet to monitor a JavaWorld server. (Here is a snapshot.) The development kit for Percollator provides the main classes that can be interfaced to many component libraries.

Gantt-like chart displays the status of the rules as reported by SE tool

The SE perforamnce Toolkit provides the ability to set rules that can be used to classify the behavior of a system into zones, Red -- busy, Green OK. For more information on how to setup and use rules look at the following two articles:

• Introduction to Percollator
• Advanced Rule Setting

The RuleStates applet produces a chart that allows a systems administrator to quickly see the status of all the rules specified in relation to one another. The horizontal axis represents increasing values of time, and the vertical axis shows rule and its respective status.

Performance measurement

The Guava runtime demonstrated some significant speed improvements over the standard JDK runtime for RuleStates.java. The results of running the test on a data set containing 911 samples are shown in the table below.

JDK 1.0.2

95 seconds

JDK 1.0.2 with Guava JIT

40 seconds

The Guava compiler provides a dramatic increase in performance and there are many applets that will benefit from this technology. Guava has implemented an efficient threading model with the its Java VM, but Guava currently does not support native methods. To improve the performance of your Java programs/applets, first calibrate your client or server by running something like CaffeineMark. Then try to understand where the time is being spent in your applet/application by using tools like ProfileViewer. Then try the various JITs on the market. Using the Guava JIT also improves your compilation speed. I am not endorsing any of the above tools. I have been able to use JITs to improve performance often.

Integrating persistence into the Percollator applet

The following discussion expands on my recent JavaWorld article, "RMI and object serialization," which discussed persistence and introduced a simple object database. The serialization examples discussed there provided directions for installing the RMI libraries. These directions need to be followed again. Don't despair: RMI will be included with JDK 1.1.

 

XpoLog Center Correlate application logs with server metrics - XpoLog

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