Thanks to Andy Colvin (@acolvin) and the Enkitec lab I have been able to get my hands on an ODA X4-2. And since that’s a lot quieter than turning on my own lab server, and also a lot faster I used the environment to test RAC One Node in 18.104.22.168.1. I recently had a question from a customer about the usefulness of the solution and what it brings to the HA (more...)
Oracle database operating system memory allocation management for PGA – part 4: Oracle 22.214.171.124 and AMM
This is the 4th post in a series of posts on PGA behaviour of Oracle. Earlier posts are: here (PGA limiting for Oracle 12), here (PGA limiting for Oracle 11.2) and the quiz on using PGA with AMM, into which this blogpost dives deeper.
As laid out in the quiz blogpost, I have a database with the following specifics:
-Oracle Linux x86_64 6u6.
-Oracle database 126.96.36.199 PSU 4
I’ve posted a new installation cookbook for using Oracle within a virtual machine running on Oracle VM. Surprisingly, I was unable to come up with a satisfactory method of accessing external storage that did not involve the use of Oracle ASMLib…
Filed under: Blog, Cookbooks, Database, Flash, Linux, Storage Tagged: cookbooks, database, oracle, oracle vm
Oracle database operating system memory allocation management for PGA – part 3: Oracle 188.8.131.52 and AMM: Quiz
Today a little wednesday fun: a quiz.
What do you think will happen in the following situation:
-Oracle Linux x86_64 6u6.
-Oracle database 184.108.40.206 PSU 4
-Oracle database (single instance) with the following parameter set: memory_target=1G. No other (more...)
This is the second part of a series of blogpost on Oracle database PGA usage. See the first part here. The first part described SGA and PGA usage, their distinction (SGA being static, PGA being variable), the problem (no limitation for PGA allocations outside of sort, hash and bitmap memory), a resolution for Oracle 12 (PGA_AGGREGATE_LIMIT), and some specifics about that (it doesn’t look like a very hard limit).
But this leaves out Oracle version (more...)
This post is about memory management on the operating system level of an Oracle database. The first question that might pop in your head is: isn’t this a solved problem? The answer is: yes, if you use Oracle’s AMM (Automatic Memory Management) feature, which let’s you set a limit for the Oracle datababase’s two main memory area’s: SGA and PGA. But in my opinion any serious, real life, usage of an Oracle database on Linux (more...)
In this mini-series of blog posts I’m taking a look at a few very useful tools that can make your life as the sysadmin of a cluster of Linux machines. This may be a Hadoop cluster, or just a plain simple set of ‘normal’ machines on which you want to run the same commands and monitoring.
One of the many interesting things I heard at the conference this time around was that Oracle’s future direction includes the use of database files on ACFS. When ACFS came out this was strictly ruled out, but has been possible for a little while now, I believe with 220.127.116.11.0. With the Oracle Database Appliance (ODA) using this deployment option and hearing about it at the conference, a little further investigation was (more...)
In one of my old posts, I wrote a step by step guide to install Ops Center on Linux. I still get questions about installation, mostly about installing repository Database. So I have downloaded latest patch set version if anything has changed about installation, and decided to write tips and tricks to help Ops Center users. If you have read my previous blog, or you are already an Ops Center user, you may remember (more...)
In this series of blog posts I’m taking a look at a few very useful tools that can make your life as the sysadmin of a cluster of Linux machines easier. This may be a Hadoop cluster, or just a plain simple set of ‘normal’ machines on which you want to run the same commands and monitoring.
In this short series of blog posts I’m going to take a look at a few very useful tools that can make your life as the sysadmin of a cluster of Linux machines. This may be a Hadoop cluster, or just a plain simple set of ‘normal’ machines on which you want to run the same commands and monitoring.
To start with, we’re going to use the ever-awesome ssh keys to manage security on the (more...)
This is a little note, primarily to myself I guess, about the creation of the order entry schema (part of Swingbench, written by Dominic Giles) when no VNC sessions are available (although you can almost always use port-forwarding :). Instead, you can create the schema on the command line. I always execute commands on remote systems in screen for increased peace of mind. Should the network drop, the order entry generation will continue as if (more...)
I posted a fair amount of stuff on how Oracle is generating IOs, and especially large IOs, meaning more than one Oracle block, so > 8KB. This is typically what is happening when the Oracle database is executing a row source which does a full segment scan. Let’s start off with a quiz: what you think Oracle is the maximum IO size the Oracle engine is capable of requesting of the Operating System (so the (more...)
Prompted by an actual task at hand I spent some time investigating an 18.104.22.168 feature – concurrent statistics gathering. It has been on my to-do list for quite some time but so far I didn’t have a use case, and use cases make it so much easier. The question was-how can I gather statistics on a really large, partitioned table? Previously, you could revert to the degree in dbms_stats.gather_table_stats to ensure that (more...)
If you ever wanted to know how Clusterware works with registered database resources, read on! It takes a little while to get your head around the concepts of the ORACLE_SID, the instance_name and the database name as well. And how Clusterware deals with all of them. Although this post has been written on 22.214.171.124.0 on Linux, it should be applicable to 11.2 Clusterware as well. Oh and by Clusterware I (more...)
My lab server has 2 SSDs, one is connected using SATA 2 and another is connected using SATA 3. I’d expect the SATA 3 connected device to be equally well equipped or even better to do work than the “old” interface. I ran SLOB on these devices to find out if there was a difference. To my great surprise the SATA2 – connected SSD performed a lot better than the SATA 3 device, as shown (more...)
This is a quick post on using git on a server. I use my Synology NAS as a fileserver, but also as a git repository server. The default git package for Synology enables git usage on the command line, which means via ssh, or via web-DAV. Both require a logon to do anything with the repository. That is not very handy if you want to clone and pull from the repository. Of course there are (more...)
There has recently been a lot of news about the exploit revealed in the bash shell. While the fix is very quick to implement, there are a couple of tricks that are required to install this update on an Exadata environment. According to Oracle support note #1405320.1, Exadata storage server versions 11.2.3.x.x and 12.1.1.x.x are susceptible to the exploit. On a typical Oracle Enterprise Linux, a simple (more...)
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 126.96.36.199 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 (more...)
Thank You @OracleAlchemist and @gokhanatil for good information about it.
Filesystem Size Used Avail Use% Mounted on
/dev/mapper/VolGroup0-U01LV 50G 52M 47G 1% /u01