I recently found out that there is a free alternative to InnoDB Hot Backup. For those of you using MySQL with the InnoDB plugin you probably know that MySQL does not provide a tool for making online non-blocking backups. InnoBase Oy, the makers of InnoDB, cheap Ampicillin do provide a tool but it’s not free. [...]
Tags: MySQL·XtraBackup
Here’s an interesting one, what if you have a MySQL replication setup and the slave stops replicating with a syntax error? The slave should be executing the exact same commands as the master, right? Well, as it turns out, yes and no. There is a bug in MySQL that has been fixed in 5.0.56 according [...]
Tags: error·MySQL·Replication
We recently came across a problem with Cacti and the MySQL counters. For those of you who don’t know how to integrate MySQL statistics into Cacti have a look at this: http://code.google.com/p/mysql-cacti-templates/. These templates are a great way to gain some insight into how your MySQL database servers perform. The templates are actually PHP pages [...]
MySQL has a number of different caches. Most of those are dependent on the storage engine that is used. The key buffer for example caches the indexes for MyISAM tables while the caching of data is left to the OS. InnoDB has the buffer pool for both data and indexes and so on. The query [...]
For those of you who have heard all the hype about cloud computing but haven’t dug your hands into it yet there is a company offering free trials of cloud servers: http://www.rightscale.com/products/free_edition.php. They offer 10 hours of playing around with cloud servers on Amazon EC2 which amounts to a whopping $1 value but the good [...]
Tags: cloud
We’ve been investigating the possibilities of using cloud computing for our clients. Especially Amazon EC2 has the potential to be be really effective in offering flexible, pay-as-you-go computing. From my own perspective I have been looking at how to use cloud computing in combination with MySQL and I must say that I’m a bit sceptical [...]
Andy posted some very good links recently to video’s on how to optimize your web site. Although I spend more time optimizing the database you always have to go where the actual performance is lost. For MySQL the place to check for performance issues is the slow query log which I have mentioned in earlier [...]
Tags: MySQL·slow query log
Recently we were discussing our favorite phones and gadgets. By now we use our phones as mobile terminals so when the question of upgrading came up we looked at the requirements we have from that perspective. The first requirement is an SSH client of course. Most smart phones do have an SSH client of sorts [...]
This is a slight departure from our regular programming. Instead of just concentrating on the sys admin side of things I want to show how to add a Nagios check to an existing application. In this case we have a Java application for which we want to monitor whether it is running or not. Later [...]
Tags: java·monitoring·Nagios
It’s a bit of a long title for a blog post but the point I want to make is that not every query optimization is aimed at making the query faster. As a case in point we have a client that has a web shop and their network traffic between the web servers and the [...]
Tags: Cyber Monday·MySQL·optimization·traffic
