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  • Oracle Linux 7 and a new YUM configuration since January 2019

    For quite some time I used to have a configuration file /etc/yum.repos.d/public-yum-ol7.repo managing my package sources in lab VMs. Today I noticed that this configuration file is deprecated, and has been replaced by a new model. This is explained in the Oracle Linux 7 administrator guide and a few other sources I totally missed. I…

  • Building your own local Oracle Linux 7 Vagrant base box

    I have been talking about Vagrant for a long time and use it extensively on my Ubuntu-powered laptop. I am using Oracle Linux 7.6 for most of my lab builds, and I like to have specific tools such as collectl, perf, and many others available when the VM boots. I als like to stay in…

  • Making some more sense of direct path reads during primary key lookups

    After having published my first article of 2019 I have received feedback I felt like including. With a nod to @fritshoogland, @ChrisAntognini and @FranckPachot. In the previous post I showed you output of Tanel Poder’s ashtop.sql as proof that direct path reads can occur even if all you do is look up data by primary…

  • Making sense of direct path reads during primary key lookups

    I recently made an interesting observation while monitoring database performance on an Oracle Enterprise Edition system. While looking at some ASH data (for which you must be licensed appropriately!) I came across direct path reads attributed to a select statement performing a primary key lookup. At first, this didn’t make much sense to me, but…

  • Little things worth knowing: the latest public-yum-ol7.repo configuration file enables an upgrade to UEK R5

    For a little while now I have been using Ansible for all installation/configuration tasks I do in the lab. I can’t really be bothered to do these things by typing commands anymore: once you get the hang of Ansible, you can develop an urge to automate everything. As part of my playbook installing the Oracle database…

  • Little things worth knowing: parallel Data Pump export in table mode

    I haven’t used Data Pump in a little while but recently needed to do a bit of work involving this very useful utility to export a single table. I know that it is possible to export data in parallel using expdp, but I can’t recall the syntax for doing so off the top of my…

  • Installing Ansible on Oracle Linux 7 for test and development use

    There are a few alternative ways of installing Ansible on Linux, and the install guide for Ansible does a great job in explaining them all in detail.  There is a potentially easier way to get to a current Ansible version if you are using Oracle Linux 7, but it comes with a very important limitation.…

  • Bootstrapping a VM image in Oracle Cloud Infrastructure using cloud-init

    At the time of writing Oracle’s Cloud Infrastructure as a Service (IaaS) offers 2 ways to connect block storage to virtual machines: paravirtualised and via iSCSI. There are important differences between the two so please read the documentation to understand all the implications. I need all the performance I can get with my systems so…

  • Enhanced “validate” commands in Oracle’s Data Guard Broker 18c

    If you are using an Oracle Database Enterprise Edition chances are that there is at least one environment in your estate making use of Data Guard. And if you are using Data Guard, why not use the broker? I have been using Data Guard broker for a long time now, and it has definitely improved…

  • Log in to Ubuntu VMs in Oracle Cloud Infrastructure

    When I learned that Oracle was providing Ubuntu images in Oracle Cloud Infrastructure (OCI) I was a bit surprised at first. After all, Oracle provides a great Enterprise Linux distribution in the form of Oracle Linux. As a Ubuntu fan I do of course appreciate the addition of Ubuntu to the list of supported distributions.…