Letsencrypt

Beware of R1 - Updated

Sven Illert - June 2, 2023

The Good Recently I discovered a critical issue when installing a new Oracle cluster for a customer on Oracle Linux systems. The hardware are shiny new blade systems and I started with the latest and greatest software components which are certified for the Oracle Enterprise Edition and Real Application Cluster. Of course the OS would be Oracle Linux 8.7 with the famous Unbreakable Enterprise Kernel which is at version 7 since this year. In April 2023 Oracle relased the release update 1 which of course brings some enhancements and fixes. Business as usual as you would think.

Instance caging vs. CPU pooling

Sven Illert - May 28, 2023

When working with Oracle databases the common recommended methods to restrict the usage of cpu resources are the so called instance caging and hard partitioning using something like Oracle Linux Virtualization Manager. The last one comes with some resource wastage though, because you have to handle multiple operating systems for multiple databases. So let’s assume that is some sort of last resort for the licensing dilemma. Instead, many of us like to have multiple databases coupled together in one operating environment and want to have some measures to tame the herd. For that there are several layers where you can put constraints on your databases, beginning with limiting the number of sessions a database can handle. But to reduce a databases cpu usage to a specific load and/or a subset of your Multi-Core/Multi-Stocket system, there currently are two methods commonly used. Look at the end of this article to see how I implemented the testing method.