Published on: Author: Michel SchildmeijerCategory: Oracle
As part of an analysis during a longer period of time, I wanted to investigate on a deeper level and for a longer period, JRockit JVM level.
Besides using WLDF embedded FlightRecording, it is also possible to separately record using jrcmd commandline. Within JRockit JDK you have this recording option you can use to take recordings for a certain period or a certain amount of time. These options are available in JRockit Command line (jrcmd.sh — a shell script shipped within your JDK installation directory).
The script collects a recording for an hour but you can set your time as you wish. Now, let’s see how the script is built up.
First, some parameters are set to identify which JVM you’d like to collect from.
Next, we define a period of time of how long recording should run, the actual jrcmd command and name of the compressed file.
We set some limits such as maxsize and compress to relieve your filesystem.
Last part of the script will take care of some cleaning up. All recorded files older than N days are removed, as well as the tmp folders on your managed server volumes!
I used a remote JRockit MC Console, in which I can see the recordings. Usually you can download them if they have a green light, but because I cleaned the tmp dir of the managed server, I needed to copy the JFR’s manually and load them into my console.
Using this approach we were able to get a day to day analysis on how applications were doing at JVM level, and we were able to solve our perfomanceproblem. The script was partly based on this article.
Michel started his career as a medical officer in the Royal Dutch Airforce, with a focus on pharma. After the air force, he continued in pharma, followed by time working in clinical pharmacology. While there, he transitioned to IT by learning UNIX and MUMPS, and developed a system for managing patients’ medical records. As his career developed, his responsibility shifted from a deep technical perspective to a more visionary role.
At the end of 2011, Michel authored a book on WebLogic Administration for beginners. He joined Qualogy in April 2012 where he expanded his repertoire significantly, serving a wide range of customers with his knowledge about Java Application Servers, Middleware and Application Integration. He also increased his multiple-industry knowledge in his role as Solutions or IT architect by working for customers in a range of sectors, including financials, telecom, public transportation and government organizations.
In 2012, he received the IT Industry-recognized title of Oracle ACE for being an ambassador and community leader in his area of expertise. In 2019, this was enhanced to Oracle ACE Director. Michel is asked regularly to speak about technology and the impact of innovation at national and international conferences such as KubeCon, Oracle OpenWorld, Groundbreakers Developers Tours and others. He contributes actively to the OpenSource community and solutions regarding containerization, CI/CD and DevOps.
In October 2021, Michel took an exciting step in his career by becoming Business Unit Manager for Qualogy Managed Services. While he still has a finger on the pulse in terms of technology, he is expanding his scope by combining his experience with the new insights gained in his new position.
Read more via blog: https://bit.ly/3fAxrqf | Medium: https://mschildmeijer.medium.com/
| Books: Oracle Weblogic Server 11gR1 PS2: Administration Essentials: https://bit.ly/3IhALmf | Oracle WebLogic Server 12c: First Look1: https://bit.ly/31olbpj
