I am very happy to announce that I have secured a great rate at a hotel for OpenSQLCamp (a free weekend conference for open source databases such as MySQL, Postgres, SQLite, and NoSQL databases). We have a room block at the Doubletree Club Hotel Boston Bayside at 24 Mt. Vernon Street in Boston at a rate of $149 per night, for single or double occupancy*, for both Friday night, October 15 and Saturday night, October 16. Wireless internet access, which is usually $9.95 per night, is included in the room fee, so there's no hidden extra there. There is also a free shuttle from Boston's Logan Airport to the hotel**. The subway is steps away from both the hotel and the venue (MIT Stata Center on the corner of Main and Vassar Streets in Cambridge). Subway fare is $2.00 each way, so if you stay at the hotel you'd have $8 extra in transportation fee.

You can reserve your room by …

Neither is ext3. Nor ext4. Nor btrfs. And thus, none of these will work on dual-Primary DRBD. Nor active-active shared storage. Nor any synchronously replicated active-active SAN. And we’re telling you very clearly.

So if you choose to ignore all warnings and put ReiserFS on dual-Primary DRBD, and mount it from two nodes, you’ve just signed up for wrecking your data. And when that happens, don’t come whining. And don’t blame DRBD or any other of the technologies you may be choosing to employ while ignoring the documentation.

…

EMT is a monitoring tool that I’ve been developing over the past few years. It’s goal is to serve as a hub for performance metrics on a single server. I’ve tried to talk about what EMT is before but I’m not a very good writer so I thought it would be best to just show people. This tutorial is going to be a quick overview of installing EMT from the rpm and a basic tutorial of it’s usage. Some of this is covered in the manual and some has changed in newer released.

Installation
The easiest way to install EMT is to grab the latest rpm from the Google Code downloads page. After installing the rpm you will see a notice about correcting some details in the default view.

Bug reports can be fun. They can also be terrible. Either way they can be entertaining. On the Drizzle IRC channel today I saw a couple references to MySQL bug reports: it is stop working and Does not make toast (which reminds me of the Mozilla bug report about the kitchen sink). Got any other favourites1?

1 This one’s for Jay.

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1. What are your favorite MySQL replication filtering rules?
2. My new favorite comic: The Adventures of …

Inspired by some recent posts about scripts for parsing mysqldump files, I thought I’d put my own little dump program out there for those looking for alternatives to mysqldump. It’s written in perl and only actually uses the mysqldump utility to dump the data portion of its file dumps. The rest is done via mysql’s internal show commands. Each database is dumped to it’s own directory, where each component in that database is dumped into five subdirs: schemas, routines, views, triggers & data. Inside these subdirs is a file per table and file per proc, etc. The data section is slightly different: as I mentioned it uses mysqldump to dump bulk insert statements into a sql file, one per table. So at any time, any or all components (including data) can be reloaded with a simple redirect or pipe back to mysql client: …

In my business (weather) we use lots map based (Geo) information.  Almost every table has latitude and longitude. Working with this kind of data can be exciting and frustrating.  This should give you a quick start into GIS with MySQL.

“A geographic information system (GIS), or geographical information system, is any system that captures, stores, analyzes, manages, and presents data that are linked to location. In the simplest terms, GIS is the merging of cartography, statistical analysis, and database technology. GIS systems are used in cartography, remote sensing, land surveying, …

I recently encountered an interesting case. A customer reported that mysqld crashed on start on OpenSUSE 11.2 kernel 2.6.31.12-0.2-desktop x86_64   with 96 GB RAM when the innodb_buffer_pool_size was set to anything more than 62 GB. I decided to try it with 76 GB. The error message was an assert due to a failed malloc() in ut_malloc_low() in ut/ut0mem.c inside InnoDB source code. InnoDB wraps the majority of its memory allocations in ut_malloc_low(), so to get an idea of the pattern of requested allocations I added a debugging fprintf() to tell me how much was being allocated and whether it was successful.

I discovered something interesting. I expected the allocation to fail on the 76 GB of the buffer pool, due to some weird memory mapping issue and a continuous block of 76 GB not being available. However, that is not what happened. 76 GB buffer was allocated successfully. What was failing is the allocation of 3.37GB after that. What in …

The binary version for MySQL Cluster 7.1.5 has now been made available at http://www.mysql.com/downloads/cluster/

A description of all of the changes (fixes) that have gone into MySQL Cluster 7.1.5 (compared to 7.1.4) can be found in the MySQL Cluster 7.1.5 Change Log.

ODTUG invited me to give a webinar and I said yes, so this Thursday you’re invited to join me as I talk about MySQL performance. We’ve come a very long way towards a MySQL that can perform well on modern hardware, and there really isn’t broad recognition of this. A lot of the best work has gone into the InnoDB “plugin” storage engine, which was announced after my co-authors and I sent High Performance MySQL to the press. I will explain what you should be doing differently now than you did two years ago, and suggest a performance-in-a-nutshell configuration baseline for MySQL that’s quite different from what I’d have said in 2008. You can register for free through GoToWebinar. See you there.

Related posts:

1. …

Lets paint the picture:

Scenario part 1 : Migrating a couple thousand stored procedures from database technology X to mysql
Scenario part 2 : Legacy system where the people who wrote it left a long time ago
Scenario part 3 : Developers sure can get real creative and invent all kinds of ways to get data (eg: having a stored proc which formulates a big query using concat after going through a bunch of conditions (fair enough), BUT the parts making up the different queries are stored in a table on a database rather than within the stored proc itself) … talk about KIS – Keep it simple!!
Scenario part 4 : This stored proc references 18 tables, 4 views, and another two stored procedures on 5 databases

Now close your eyes and try to imagine that for a few seconds, nah kidding don’t want you to hurt yourself.

I wonder, who’s gonna cover my health insurance if i go crazy? :)

mysql 02:55:47 DEV …