RAM is the new disk – and how to measure its performance – Part 3 – CPU Instructions & Cycles

If you haven’t read the previous parts of this series yet, here are the links: [ Part 1 | Part 2 ].

A Refresher

In the first part of this series I said that RAM access is the slow component of a modern in-memory database engine and for performance you’d want to reduce RAM access as much as possible. Reduced memory traffic thanks to the new columnar data formats is the most important enabler for the awesome In-Memory processing (more...)

Linux Kernel Stack Profiling and Flame Graphs Applied to Oracle Investigations

Topic: This blog post is about kernel stack profiling and visualization with flame graphs with examples.

Stack profiling and flame graphs are very useful techniques and tools for troubleshooting and investigating workloads at the OS-level and understand which code path take most of the execution time. You can find extensive material and examples o flame graphs in Brendan Gregg's website and blog. A few additional examples of using stack tracing and flame graphs for (more...)

OEL/RHEL 7 – firewalld

How cool is getting Linux. Hope soon to not look like a Windows. If they put a butterfly or shiny window in the “start menu” I’m out of the game. The “new” firewalld is cool and dynamic, but my servers are square, boring and static. Maybe if I’m using RHEL/OEL 7 in my laptop it […]

SLES shell script to check required os packages according to documentation before starting oracle forms & reports installation

Hi!

If you try to install oracle forms & reports 11.1.2.2 on SLES 11.3 than despite all installer checks are passed maybe you get a message like:

Error in invoking target ‘install’ of makefile ‘<FR_HOME>/sqlplus/lib/ins_sqlplus.mk’.

The reuirement check of the installer shows only missing openmotif classes which are not really required on SLES (see Doc ID 1567715.1), but no problems with a compiler or something similar.


Checking for binutils-2.19-11. (more...)

Web Pages Not Databases – Part 2: Fail2ban, Apache, IP Addresses, Linux, SELinux

August 23, 2015 (Back to the Previous Article in this Series) I started using Linux in 1999, specifically Red Hat Linux 6.0, and I recall upgrading to Red Hat Linux 6.1 after downloading the files over a 56k modem – the good old days.  I was a little more wise when I upgraded to another […]

Preparing a Oracle Linux for a Vagrant box

This post is an overview of an installation and configuration process of the Oracle Linux, which will be used as a machine “box” for Vagrant software using a Virtual Box platform.

Post itself is divided into two parts:

  1. Oracle Linux installation (points 1 to 12)
  2. Vagrant box configuration (points 13 to 16)

Part 1 – Oracle Linux installation

 

1. Create a new Virtual Machine - machine name will be used later to create Vagrant (more...)

The Leap Second is No Laughing Matter (if you have java on an older Linux kernel)

Earlier this month we began getting frequent email warnings from our EM12c server that some agents were experience read time outs. Then we saw that the emagent java process was using A LOT of CPU, regularly around 500% but sometimes as high as 800% as seen from "top". Restarting the agent did nothing.

I opened an SR with Oracle Support, where I was first instructed to apply a JDBC patch and then a PSU agent (more...)

Installing Oracle XE, ORDS and Apex on CentOS – Part Four: Stress testing

This is part four in a series of blog posts about how to install Oracle 11g Express Edition (XE) with Oracle Application Express (Apex) on a CentOS Linux server, with Apex served by Oracle REST Data Services (ORDS) running on top of Tomcat and Apache.

After setting up a small CentOS server with Oracle Express Edition (XE), I wanted to stress test it to see how much load such a barebones installation can handle. In (more...)

Installing Oracle XE, ORDS and Apex on CentOS – Part Three: Additional configuration

This is part three in a series of blog posts about how to install Oracle 11g Express Edition (XE) with Oracle Application Express (Apex) on a CentOS Linux server, with Apex served by Oracle REST Data Services (ORDS) running on top of Tomcat and Apache.

By now, you should have a working installation of CentoOS with Oracle XE, Apex, ORDS, TomCat and Apache. There are still some additional configuration and optimization we should do, which (more...)

Installing Oracle XE, ORDS and Apex on CentOS – Part Two: Installation

This is part two in a series of blog posts about how to install Oracle 11g Express Edition (XE) with Oracle Application Express (Apex) on a CentOS Linux server, with Apex served by Oracle REST Data Services (ORDS) running on top of Tomcat and Apache.

Let's get right to it, starting with Oracle XE.

Installing Oracle XE

This is actually quite straightforward, assuming you have followed the prerequisite steps in part one.



As part of (more...)

Installing Oracle XE, ORDS and Apex on CentOS – Part One: Preparation

This is part one in a series of blog posts about how to install Oracle 11g Express Edition (XE) with Oracle Application Express (Apex) on a CentOS Linux server, with Apex served by Oracle REST Data Services (ORDS) running on top of Tomcat and Apache.


Provisioning the server


First of all, we need a server to install the software on. There are many hosting providers that offer cheap Linux servers. I have been trying out (more...)

Installing Oracle XE, ORDS and Apex on CentOS

I am writing a series of blog posts about how to install Oracle 11g Express Edition (XE) with Oracle Application Express (Apex) on a CentOS Linux server, with Apex served by Oracle REST Data Services (ORDS) running on top of Tomcat and Apache.

This is perhaps better explained with an illustration of the setup:

Best of all, this setup consists only of free (license-free) software, and as you will see in this series of blog (more...)

How to configure Link Aggregation Control Protocol on Exadata

During a recent X5 installation I had to configure Link Aggregation Control Protocol (LACP) on the client network of the compute nodes. Although the ports were running at 10Gbits and default configuration of Active/Passive works perfectly fine the customer wanted even distribution of traffic and workload across their core switches.

Link Aggregation Control Protocol (LACP), also known as 802.3ad is a methods of combining multiple physical network connections into one logical connection to increase (more...)

RHEL6 udev and EMC PowerPath

I’m working on Oracle database migration project where customer have chosen commodity x86 hardware with RHEL6 and EMC storage.

I’ve done many similar installations in the past and I always used the native MPIO in Linux (DM-Multipath) to load balance and failover I/O paths. This time however I’ve got EMC PowerPath doing the load balance and failover and got the native MPIO disabled. From my point of view it’s the same, whether I’ll be using (more...)

runInstaller fails at CreateOUIProcess with permission denied

Just a short post on a problem I encountered recently.

I had to install 11.2 GI and right after running the installer I got a message saying permission denied. Below is the exact error:

[oracle@testdb grid]$ ./runInstaller -silent -showProgress -waitforcompletion -responseFile /u01/software/grid/response/grid_install_20140114.rsp
Starting Oracle Universal Installer...

Checking Temp space: must be greater than 120 MB.   Actual 7507 MB    Passed
Checking swap space: must be greater than 150 MB.   Actual 8191 MB     (more...)

#FISMA Ready @Ubuntu LTS @18F

Ubuntu is a very popular operating system (OS) in the cloud space but the Federal government has been reluctant to adopt Ubuntu, preferring to stick with Redhat as their Linux flavor of choice.  As the Government moves toward the cloud it makes sense to me that Ubuntu would start to see some more play time.  One of the big hurdles to this is the need to ensure that Ubuntu meets the Federal Information Security Management Act (more...)

Exadata and Bash Shellshock

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...)

Where is my space on Linux filesystem?

Not Often, I checked about my space after made filesystem on Linux. Today, I have made Ext4 filesystem around 460GB, I found it 437GB only. Some path should be 50GB, but it was available only 47GB.
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

Reference  - (more...)

Extend linux partition on vmware

It was a quiet day, I worked as System Administrator and installed Oracle Linux on Virtual Machine guest. After installed Operating System, I wanted to extend disk on guest. So, I extended disk on guest. Anyway, I came back in my head what I was supposed to do on Linux then ? 
- Create new disk (and Physical Volume) and then add in Volume Group.
Checked my partition:
[root@mytest01 ~]# fdisk -l (more...)

Switch CentOS to Oracle Linux – centos2ol.sh

My time has used much with Linux. Some people asked to move from CentOS to Oracle Linux somehow. I used to believe it easy to do like that. Anyway, It'd better to test. 
I focused on 2 links.
https://linux.oracle.com/switch/centos/
http://docs.oracle.com/cd/E37670_01/E37355/html/ol_switch_yum.html

Oracle introduces centos2ol.sh script that can convert CentOS 5 and 6 systems to Oracle Linux. After that run "yum upgrade" again.
[root@test-centos ~]# uname -r
2.6.32-431.29. (more...)