Some of you might have followed the discussion around the number of standby redo logs on twitter, but since 140 characters are woefully short for the complete story here’s the writeup that prompted the question. This is a test with 188.8.131.52 on virtualised Linux, repeated on a proper platform with physical hardware.
First of all here’s my setup. I have a dbca-based database (CDB, but doesn’t matter) that features 3 groups for its online redo logs. They are all 50 MB in size-important for this test, but not realistic :) Following the Oracle documentation I created n + 1 groups (per thread) on the standby to stop Data Guard broker from complaining about missing standby redo logs (SRL).
The end result was positive, here’s what the broker thinks:
Followers of my blog and website know I play around with installations on Fedora for fun. All of my installation guides on Fedora come with a link at the top that points to this disclaimer.
A few times recently I’ve been contacted by people saying their boss, teacher or customer is insisting they install Oracle on Fedora. Rather than repeat myself, I’ve added another point at the bottom of this disclaimer that reads:
This post looks like I am jumping on the bandwagon of IT orchestration like a lot of people are doing. Maybe I should say ‘except for (die hard) Oracle DBA’s’. Or maybe not, it up to you to decide.
Most people who are interested in IT in general will have noticed IT orchestration has gotten attention, especially in the form of Puppet and/or Chef. I _think_ IT orchestration has gotten important with the rise of “web scale” (scaling up and down applications by adding virtual machines to horizontal scale resource intensive tasks), in order to provision/configure the newly added machines without manual intervention, and people start picking it up now to use it for more tasks than provisioning of virtual machines for web applications.
(the details are investigated and specific to Oracle’s database implementation on Linux x86_64)
Exadata IO: This event is not used with Exadata storage, ‘cell single block physical read’ is used instead.
Despite p3 listing the number of blocks, I haven’t seen a db file sequential read event that read more than one block ever. Of course this could change in a newer release.
This is probably as much a note-to-self as it can possibly be. Recently I have enjoyed some more in-depth research about how the Linux kernel works. To that extent I started fairly low-level. Theoretically speaking, you need to understand the hardware-software interface first before you can understand the upper levels. But in practice you get by with less knowledge. But if you are truly interested in how computers work you might want to consider reading up on some background. Some very knowledgable people I deeply respect have recommended books by David A. Patterson and John L. Hennessy. I have these two:
Oracle 184.108.40.206 is out, after lots of announcements the product has finally been released. I had just extended my 220.127.116.11.3 cluster to 3 nodes and was about to apply the July PSU when I saw the news. So why not try and upgrade to the brand new thing?
What struck me at first was the list of new features … Oracle’s patching strategy has really changed over time. I remember the days when Oracle didn’t usually add additional features into point releases. Have a look at the new 18.104.22.168 features and that would possibly qualify to be 12c Release 2…
In summary the upgrade process is actually remarkably simple, and hasn’t changed much since earlier versions of the software. Here are the steps in chronological order.
I don’t know how often I have type ./ruinInstaller instead of runInstaller, but here you go. This is the first wizard screen after splash screen has disappeared.
I did a quick update of my Oracle installation articles on Oracle Linux 7. The last time I ran through them was with the beta version OL7 and before the release of 22.214.171.124.
The installation process of 126.96.36.199 on the production release of Oracle Linux 7 hasn’t changed since the beta. The installation of 188.8.131.52 on Oracle Linux 7 is a lot neater than the 184.108.40.206 installation. It’s totally problem free for a basic installation.
You can see the articles here.
With all the excitement around the release of Oracle Database 12.1.02, it’s easy to forget that there is other stuff going on as well.
Just remember, it takes quite a while to get products certified on this stuff, so although I’ve already tried installations on the beta versions, I would not install any Oracle products on this stuff “for real” until the official certification is announced for each product.
I had an interesting discussion as part of my latest presentation at the UKOUG RAC CIA & Database Combined SIG. Part of my talk was about the implications of the new threaded execution model in Oracle.
Since “we do not use Windows” (except for gaming) I can’t compare the Windows thread model to the new 12c implementation on UNIX. There are however interesting implications when switching to the new model, some of which I’d like to demonstrate here. First of all, threaded execution is not enabled by default. With 220.127.116.11.3 on top of Oracle Restart you get the either all or a subset of the following background and auxiliary processes for a CDB:
Direct NFS is a great feature that I have finally had the time to investigate further. Since I always forget how to set it up and I didn’t find blog posts about this subject elsewhere I decided to put something together.
In this configuration I am using a virtual machine named server1 to export a directory to server2. Oracle is not as lenient as myself and may have certain support requirements when it comes to dNFS servers but I just wanted to get started.
The export of the NFS mount is shown here: