Yesterday I spent some time trying to figure out how I can better support people who are running OSX. I came to the conclusion that it’s not possible for me to do this, and in fact, Apple doesn’t want me to. As part of that process, it made me rethink OpenSolaris a little bit. Here’s my list of things I like about OpenSolaris:

• It’s not OSX
• I can install it in a VM
• It’s trying to get packaging right
• It’s Free Software

Caveats to the above list:

• My reservations about a brand new ZFS-based packaging system
• It may be Free Software, but it’s CDDL

Thank you Sun, for not being the cess-pool of arrogant wanks that Apple is!

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The purpose of this post is to outline a general flow-chart for improving the performance of queryies in MySQL. Much has been written on using EXPLAIN to optimize queries, but there is a whole process that should be followed in order to maximize the effectiveness of query performance tuning. Following is a visual [...]

Today I’ve managed to finish initial version of our bounces-handler package we use for mailing-related stuff in Scribd.

Bounces-handler package is a simple set of scripts to automatically process email bounces and ISP‘s feedback loops emails, maintain your mailing blacklists and a Rails plugin to use those blacklists in your RoR applications.

This piece of software has been developed as a part of more global work on mailing quality improvement in Scribd.com, but it was one of the most critical steps after setting up reverse DNS records, DKIM and SPF.

The package itself consists of two parts:

• Perl scripts to process incoming email:
  • bounces processor — could be …

When I moved to the UK from Italy, now more than eight years ago, people asked me all the time "Why did you leave such a sunny place like Italy to move to England?". Well, first of all, the south east of England is not that bad. There is a decent number of sunny days in a year and the bright sky of a breezy morning is just fantastic. Second, my home town is Milan, in the middle of the Po valley, with foggy winters and humid summers, with temperatures between -15C and +38C over the year. And there is another point: no wind and no much rain, hence pollution. In Milan the pollution is so awful that almost one third of the working days in a year private cars cannot be used within the city, in the attempt of reducing emissions. When I was a child, my mum used to put a PVC cover over the washing line to avoid that clean clothes would get immediately dirty.

It is a long introduction, but it is probably worth it, because it fits almost …

Quite frequently I see customers looking at recovery as on ability to restore data from backup which can be far from being enough to restore the whole system to operating state, especially for complex systems.

Instead of looking just at data restore process you better look at the whole process which is required to bring system to the working state, including data consistency requirements and times. This has to be considered for different data loss scenarios which may happen.

Let us look at simple example - a master with 1TB of database size replicating to 50 servers in 5 different Data Centers via single Replication Relay server in each. Forget the single point of failure for the second and just think what problems we may have to deal with.

First lets look at the master. What may happen to it ? We can have Master having soft crash in which case it will be unavailable for some time but we can get all the …

Have you ever seen the replication stopped with message like this:

Last_Error: Could not parse relay log event entry. The possible reasons are: the master's binary log is corrupted (you can check this by running 'mysqlbinlog' on the binary log), the slave's relay log is corrupted (you can check this by running 'mysqlbinlog' on the relay log), a network problem, or a bug in the master's or slave's MySQL code. If you want to check the master's binary log or slave's relay log, you will be able to know their names by issuing 'SHOW SLAVE STATUS' on this slave.

This is relay relay log corruption and you can check details in the MySQL Error log file. The error message describes few reasons and indeed because there is little validation (ie no checksums) in the replication there are multiple reasons for bad event to show up in relay logs.

Really this is only one of various error messages you could see if relay log corrupted. You …

My post about contributing to Drizzle somehow ended up with a very old posting date to MySQL Planet.MySQL DBA & Programming Blog by Mark Schoonover

Let me begin by saying “I am so not a gadget guy.” I don’t have an iPhone. Heck, I didn’t have a cellphone at all until April when I joined Percona as a consultant. I don’t ooh and aah over other people’s gadgets most of the time. I don’t have, you know, that kind of envy. I’m sure you see where this is going: I got a gadget and I think it’s really cool.

Anyway, my wife and I have a bunch of computers (desktops and laptops) and we had been feeling the pain for a long time: the files were only on one computer, and we wanted them available. I built a file server and then realized that it was going to be really expensive in terms of power alone, so I went back to USB drives for backups, and kept thinking about it.

After a long time I …

Not really, it's about 90 degrees out and sunny here near San Diego. For a couple of years, I've been looking around to volunteer on an OSS project, and Drizzle really fits the bill. I've used MySQL for years, and have done some community support as well. I've been wanting to gain greater experience in technical writing, so Drizzle is the perfect project.

I'll be working on development & user documentation, and the weekly Drizzle Report. The Drizzle Report is a weekly synopsis on development and other progress to be posted on my blog Sunday evenings.

Be sure to check out the Drizzle Wiki. Launchpad is the home of the Drizzle project.

MySQL DBA & Programming Blog by Mark Schoonover