Crossplatform transportable tablespaces – part 1

Database Management and Performance
| Jul 16, 2014
There is couple of way to do heterogeneous migration of Oracle databases but staring with 12c there is whole set of new RMAN commands to transport data across different platforms.
I was looking for a best method of move tablespaces from HP-UX to Linux and after some research I found this presentation by Martin Bach from Enkitec (you can watch it online here). Martin describing Oracle Perl script (MOS ID 1389592.1) which allows (more...)

Don’t delete your flashback logs manually

Database Management and Performance
| Jul 1, 2014
What happen when someone will delete Oracle flashback logs ? You probably don't notice it until you will try to flashback database or bounce instance. 
There is no hope for flashback database without flashback files but there is still way to start your database again without recovery or data loss.

Here is a scenario:
[oracle@dev-6 alert]$ sqlplus / as sysdba

SQL*Plus: Release 11.2.0.4.0 Production on Tue Jul 1 09:34:18 2014

Copyright  (more...)

Top Linux processes and Oracle

Database Management and Performance
| Jun 26, 2014
Today due to application bug I had to check several time mapping between Linux PID processes and Oracle sessions. With small BASH script this is quite easy now
#!/bin/bash

# ps doesn't show real time CPU usage but average - skewed for long running processed
#TOP5=`ps xo pid --sort pcpu | tail -5 | xargs echo | sed -e 's/\s/,/g'`
TOP5=`top -b -d 1 -n 1 | head -12 | tail -5 | awk  (more...)

Rolling upgrads using logical standby database.

Database Management and Performance
| Jun 24, 2014
Couple of weeks ago there was a Twitter discussion started by Martin Bach (@MartinDBA) about cases for logical standby implementation. A rolling upgrade was mentioned by Tim Gorman (@timothyjgormanas) as one of potential recommendations for using this rare use product. I have been involved in such project in the past and I prepared an instruction and did quite large number of rolling upgrades from 11.1 into 11.2.

There are couple of my “gotchas”

Grid Infrastructure upgrade to 11.2.0.4 on AIX – always read log files

Database Management and Performance
| Apr 5, 2014
Oracle Restart 11.2.0.3 and same version of database has to be upgraded into 11.2.0.4. Looks like quite easy task but I hit some problems with it.

I had 31.9 GB free and OUI through error about disk space. Fair enough cause it also proposed a parameter to ignore it. Current version of GI (11.2.0.3) occupied around 25 GB so i though it will be OK (more...)

Automated Linux VM build on ESX

Database Management and Performance
| Mar 19, 2014

How to automatically install RedHat like (Red Hat, Cent OS, Oracle Enterprise Linux) Linux system on ESX or VirtualBox servers ? There are at least two methods. I have seen VM cloning in lot of places using ESX (VSphere Center) or VirtualBox functionality. Cloning is fine but it required some intervention after clone will be finished (like host rename or IP address change). What if we want to install different releases of systems - well it (more...)

OraSASH visualization

Database Management and Performance
| Oct 25, 2013

Hello,

I started working on that project 2 years ago and at that stage I created a JavaScript code to display real time graphs and parse JSON code. The backend providing JSON data from Oracle Database was based on PHP and I didn't like that solution as it required to (more...)

New release candidate of OraSASH

Database Management and Performance
| Oct 25, 2013
Hi,

 There is a new release candidate of OraSASH 2.4 available on github - https://github.com/pioro/orasash/tree/v2.4-rc2

 This version is providing much more views and it's easier to use your existing AWR queries against OraSASH. 

regards,
Marcin 

How to improve VMware performance on your PC

Database Management and Performance
| Jul 30, 2013
I found very interesting post here - VMware Performance Enhancing Tweaks (Over-the-Counter Solutions). I used it on my VMware Player and Workstation and when I disabled vmem file my laptop it stopped blinking HDD led for 5 - 10 min every time it wake up from sleep mode.

 regards,
Marcin

DataGuard – Far Sync – part 12 – Data Guard Broker

Database Management and Performance
| Jul 28, 2013
Oracle introduced Far Sync Data Guard configuration which I described briefly in this post. Now is time for part two and using Data Guard Broker to add Far Sync instance.
Assuming that you have basic Data Guard Broker configuration ready (as described in - How to quickly build standby database (more...)

How to quickly build standby database and setup DataGuard configuration using Oracle 12c

Database Management and Performance
| Jul 27, 2013
With every release of Oracle database there are new possibilities to build a required solution (ex. standby database) faster and with fewer steps. This is not official guide but rather a mix of Oracle 12c functionality used to build DataGuard configuration using RMAN and DataGuard Broker.

Assumptions:

DataGuard – Far Sync – part 1 – simple configuration

Database Management and Performance
| Jul 16, 2013
Oracle introduced a new feature for DataGuard called Far Sync. This configuration is design to support synchronous redo transport between primary and standby database which are far apart. In usual configuration synchronous redo transport between data centre in Europe and US is possible but inefficient from the primary database performance (more...)

Oracle 12c – incremental backup for DataGuard over network

Database Management and Performance
| Jul 9, 2013
If you have DataGuard or standby database in your organization you probably will love that new RMAN feature. Since 12c it is possible to catchup standby database using incremental backup using one command. Additional space and time need to run incremental backup, copy over to standby and restore can be (more...)

PL/SQL function in SQL – short example – Oracle 12c

Database Management and Performance
| Jun 29, 2013
This is my first post about Oracle 12c. When I first time heard about PL/SQL functions inside SQL my first thought was - can I use it in my topaas.sql script to run it in loop ? I decided to give PL/SQL functions in SQL a quick try to and (more...)

DataGuard FastStart Failover configuration with Oracle Wallet

Database Management and Performance
| Jun 7, 2013
Last two months were very busy for me with lot of work and moving house as well. There is a lot of thoughts in my head I want to write about but some of them have to wait until my lab will be online again.Recently I was working on (more...)

dbms_dnfs and clone.pl

Database Management and Performance
| Mar 29, 2013
If you are using to use dbms_dnfs to clone your database as described in MOS note 1210656.1 or on Tim's Hall blog - Direct NFS (DNFS) Clonedb in Oracle Database 11g Release 2 (Patchset 11.2.0.2) and your database version is 11.2.0.3 there is (more...)

Next OakTable 2012 video is online

Database Management and Performance
| Mar 20, 2013
Hi,

 This time Alex Gorbachev presentation about ASM failures - next videos on the way.

regards,
Marcin

New OakTable World 2012 video is published

Database Management and Performance
| Mar 3, 2013
Just published Kevin Closson video from OakTable World 2012.
Enjoy,

 Marcin

Oracle on AIX – where’s my cpu time ?

Database Management and Performance
| Feb 21, 2013
This story begins couple of weeks ago when I was asked to look on performance problem for critical processes before go-live. There were differences between run times between different test systems and between runs with 10046 trace enabled or not.

First of all I started with tracing issue. I have checked server CPU and disk utilization using NMON (tool name is important here). There wasn’t any problem with CPU utilization – or at least this is what I was thinking at that time. Tracing was enabled with level 12 (bind and wait) and it generate 2 GB of trace file (more...)

OakTable World 2012 – Greg Rahn video

Database Management and Performance
| Feb 9, 2013
New video from OakTable World 2012 is available - Greg Rahn - Beyond Relational Databases

 

regards
Marcin