Isuru's Blog

For at least 2 years, I wanted make a "cheat sheet" for some of the popular Performance Observability Tools in Linux. Today, I could finally publish a Medium story about " Linux Performance Observability Tools "

When you are using Java Flight Recorder (JFR), the JFR will use an event settings file to check which event types to record. By default in JFR, there are two settings, "default" and "profile". The default setting is recommended for Continuous Recordings as it has very low overhead (typically less than 1% overhead). The profile setting has more events and useful when profiling the application. As mentioned in my previous blog post regarding  Java Flight Recorder Continuous Recordings , we use following arguments to do a Continuous Recording. -XX:+UnlockCommercialFeatures -XX:+FlightRecorder -XX:FlightRecorderOptions=defaultrecording=true,disk=true,repository=./tmp,dumponexit=true,dumponexitpath=./ Note: According to the Oracle documentation on " java " command, we should be able to specify "settings" parameter to the -XX:FlightRecorderOptions. However, the settings parameter has no effect when used with the -XX:FlightRecorderOptions and ...

I wanted to find out the processor details in my laptop and I found out that there are several ways to check. For example, see The RedHat community discussion on  Figuring out CPUs and Sockets . In this blog post, I'm listing few commands to find out details about CPUs. I'm using Ubuntu in my Lenovo ThinkPad T530 laptop and following commands should be working any Linux system. Display information about CPU architecture $ lscpu Architecture: x86_64 CPU op-mode(s): 32-bit, 64-bit Byte Order: Little Endian CPU(s): 4 On-line CPU(s) list: 0-3 Thread(s) per core: 2 Core(s) per socket: 2 Socket(s): 1 NUMA node(s): 1 Vendor ID: GenuineIntel CPU family: 6 Model: 58 Model name: Intel(R) Core(TM) i7-3520M CPU @ 2.90GHz Stepping: 9 CPU MHz: 1199.988 CPU max MHz: 3600.0000 CPU min MHz: 1200.0000 BogoMIPS: ...

I am learning about Linux Performance Tools and I found Brendan Gregg 's talks on Linux Performance  are very interesting. There are so many performance tools for Linux. Brendan recommends to follow a performance analysis methodology  to analyze system or application performance. These methodologies can guide us to choose and use these performance tools effectively. Linux Performance Observability Tools There are different types of command line tools available in Linux. In this blog post, I'm going to focus on Linux Performance Observability Tools . I highly recommend to watch Brendan's talk at Velocity 2015 on Linux Performance Tools and I took details about following tools from his presentation and his website. Linux Performance Observability Tools Taken from Brendan Gregg's Website:  http://www.brendangregg.com/Perf/linux_observability_tools.png Here are some examples of using Linux Performance Observability Tools in Ubuntu.  I tested each of th...

Last year, I got two opportunities to talk about Java Mission Control & Java Flight Recorder. I first talked about " Using Java Mission Control & Java Flight Recorder " as an internal tech talk at WSO2 . I must thank Srinath for giving me that opportunity. After that, Prabath also invited me to do a talk at Java Colombo Meetup . Prabath, Thank you for inviting me and giving me the opportunity to talk at the Java Colombo Meetup! I'm also very excited to see that Marcus Hirt , the Team Lead for Java Mission Control has mentioned about the Java Colombo Meetup in his blog post: " My Favourite JMC Quotes ". It's so nice to see "Sri Lanka" was mentioned in his blog post! :) From Marcus' Blog Here are the slides used at the meetup. Java Colombo Meetup: Java Mission Control & Java Flight Recorder from Isuru Perera Marcus Hirt's blog posts really helped me to understand JMC & JFR concepts and his t...