When issues occur with some JVM application, it can be useful to do some capturing of JVM events using built-in flight recorder. Load imposed by JFR can be controlled by profiles, and usually it’s from 5-15% for normal usage (unless... Read more
Sometimes during inspection of production problems it can be very useful to enable JMX endpoint on running JVM process. To do this, perform the follow commands as process user. To enable JMX with flags during process tartups Read more
In this post we will go through the process of writing a custom STM32303RE bootloader. We will use the reference manual to find out all relevant details and use STM32CubeIDE for development. The actual board used during the development is... Read more
When working as a system admin I often had a problem where the python application got stuck but was unsure where. To handle this case I created a GDB script that retrieved that backtrace. These scripts refere to older versions... Read more
I had a case where I got an table id but was not sure what table was it refering to. I known that table contained string ‘test’. I knew that PostgreSQL has support for for selects and also supports execute... Read more
When writing Avro schema I often forget the how to construct certain constructs which are provided by Avro Schema itself. For my own sake I decided to keep a list of often used features. Union types and null Union types... Read more