To make life a little easier at home and work I've put together a simple enough script that is run by cron to tally up statistics like: Innodb_data_reads, Innodb_data_writes, Qcache_hits, Qcache_inserts, Questions, Open_files and Open_tables over time (I sample every hour) with the ability to easily expand and add your own `show status` variables.

Next I'll create some nice graphical interface so it's more obvious how the server or cluster is running. You can grab the script over at my CV hosting. Note that actual client writes in a master master environment would be (writes / number of servers) roughly, very roughly. If you have any ideas for countering this please let me know.

Enjoy.
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Copyright 2006-2008 Andrew Rose [rose.andrew@gmail.com] [andrewrose.co.uk]

I just learned from my colleagues in our Dublin office that Mårten Mickos, CEO of MySQL AB will be visiting them this coming weekend. They would like to take this opportunity to arrange a MySQL User Group Meeting, which will take place on Saturday, 27th of January, 18:00 o'clock in their offices:

MySQL Ireland,
Ground Floor, Misys Building,
Eastpoint Business Park,
Dublin 3
Ireland

This is your chance to meet and talk with Mårten and other MySQLers. There will also be free food and drinks and most likely a tech talk about MySQL (details will follow). So if you are located somewhere around Dublin, make sure to attend this event!

Thanks to MySQL, and in particular Jay, for giving me the opportunity to talk about PBXT at the up-coming MySQL Conference in April. I will be presenting a session with the title: PrimeBase XT: Design and implementation of a transactional storage engine.

Topics include the design of XT and how it differs from conventional implementations, experience with implementing storage engines, surprises and gotchas, and performance. So I think this talk will be of interest to both end-users and other developers of storage engines.

See you there!

If you ever get something like this:

bk clone -lq ndb bug25567

clone: unable to readlock /home/stewart/Documents/MySQL/5.1/ndb

then try this:

bk unlock -s

to remove stale locks.

I have no idea how anybody is meant to come to the command from the error message… blindly guessing ‘bk help unlock’ worked for me though.

In both Oracle and MySQL, you can do:

create table T1 as select * from T1

This CREATE TABLE AS statement basically clones table T1 with its structure and data in T2. This can be pretty handy at times.

The equivalent of that in Sql Server is SELECT INTO. For example, you can do:

select * into T2 from T1

to achieve similar results.

We just published the results of Amanda usage survey and I want to share my personal observations.One of the most inspiring findings is that 95% of respondents would recommend Amanda to a friend. The Loyalty expert Fred Reichheld would be very impressed with such a result. The overall satisfaction with Amanda is also highlighted by the fact that 70% of respondents have been using Amanda for more than 2 years. People use software for such a long time only if it does the job well. Many users reported that Amanda was up to the task recovering files in most critical situations.

I think it is just great that more than 60% of users provided suggestions for new functionality.

Working with Calvin today I took some changes that Trudy had made to ha_example and a couple of fixes Brian Miezejewski made to the skeleton tree and pushed them.

You can download the skeleton here:
http://hg.tangent.org/skeleton-mysql-engine?ca=tip;type=gz

The skeleton is a "one stop startup" for creating a storage engine under MySQL. It has all of the moving parts for an autoconf project setup for you and it includes the example engine to play with. This is not an official project at MySQL just a nice have for people who are interested in getting up and running with a new storage engine quickly.

Calvin is looking at adding support for Windows for plugin builds so that Windows developers can quickly come up to speed in developing engines.

It will make Microsoft's job a bit easier when they …

I recently had a chance to chat with Nora Denzel, former Senior Vice President and General Manager of the Software Global Business Unit of Hewlett Packard, to talk shop about IT operations management and open source's role / opportunity in the space. Here's a snippet of the QA.

Open Sources: How big is the IT monitoring/management space today? Who are the major players that occupy it?

Denzel: In 2006, Gartner released a study that pegged the IT operations management software market at about $7 billion a year with more than 50% of the number going towards IT infrastructure monitoring and management. The dominant legacy players that offer proprietary monitoring solutions are the usual suspects - HP OpenView, IBM Tivoli, CA Unicenter, and to a lesser extent BMC Patrol. Their software is filled to the gills with features, which often goes unutilized I'd like to point out, and is very expensive.

Open …

As any serious MySQL DBA knows, MySQL can and will now and again go out of sync, most of the time it cures itself, but sometimes the worst happens and a slave stops replicating. Yet I bet most apps keep on going with random outcomes, especially if your storing the users sessions in MySQL and have a mastermaster setup.

To counter this problem I implemented a quick an easy check. If the check catches a replication failure `touch` a file to the nfs mounted tmp directory that is shared by all nodes.

Each node before executing anything (in index.php) checks for a file called 'halt' in tmp. If found exits and bingo no weirdness, corruption, or wondering why something is there one click, gone the next. It even emails you, and with a simple addition can sms.

mysql_query("show slave status;", CONNECTION);
if(mysql_errno(CONNECTION)!=0)
{
   mail('team@<some url>',
 …

I stumbled across this on the fabulous http://www.everythingsysadmin.com :

from:  http://www.socallinuxexpo.org/wios07/

The Southern California Linux Expo (SCALE) will host a Women in Open Source Event as part of their upcoming 2007 conference, SCALE 5x.

The focus of this event is on the women in the open source and free software communities. The goal of this event is to encourage women to use technology, open source and free software, and to explore the obstacles that women face in breaking into the technology industry. The Women in Open Source event will be held on February 9, 2007 at the Los Angeles Airport Westin Hotel.

I have seen the dearth of women, in system administration as …