Introduction

One of the features that make MySQL so great is its easy replication set-up. If you are experienced and know-how to do it, it takes you about 15 minutes to set-up a slave. What you have in the end is a replication from one master to one or several slaves. So you can build a top-down data stream pyramid and spread your data on many slaves.


From time to time some customers are asking for the other way: Many masters replicating to one slave (which is also called multi-source replication). For this requirement MySQL replication cannot help you directly.

Possibilities

You can circumvent this situation in the following ways:

1. 
   
2. Implement your own data transfer mechanism.
   
3. Use …

Was scanning through the facebook team’s engineering blog recently.  Although it’s not updated very frequently, there’s some good technical discussion of the engineering behind Facebook, and what it takes to make the site work.

In particular I found this discussion Scaling Out by Jason Sobel.   He talks about the cache coherency challenges they had, and how they used MySQL & memcache to get the job done.

We use valgrind to find memory leaks in MySQL on Linux. The tool is a convenient, and often enlightening way of finding out where the real and potential problems are location.

On Windows, you dont have valgrind, but Microsoft do provide a free native debugging tool, called the user-mode dump heap (UMDH) tool. This performs a similar function to valgrind to determine memory leaks.

Vladislav Vaintroub, who works on the Falcon team and is one of our resident Windows experts provides the following how-to for using UMDH:

1. Download and install debugging tools for Windows from here
   MS Debugging Tools
   Install 64 bit version if you’re on 64 bit Windows and 32 bit version
   otherwise.

2. …

Find out about Sun's new 4-chip UltraSPARC T2 Plus system direct from the source: Sun's engineers.

Sun today announced the 4-chip variant of its UltraSPARC T2 Plus system, the Sun SPARC Enterprise T5440. This new system is the big brother of the 2-chip Sun SPARC Enterprise T5140 and T5240 systems released in April 2008. Each UltraSPARC T2 Plus chip offers 8 hardware strands in each of 8 cores. With up to four UltraSPARC T2 Plus chips delivering a total of 32 cores and 256 hardware threads and up to 512Gbytes of memory in a compact 4U package, the T5440 raises the bar for server performance, price-performance, energy efficiency, and compactness. And with Logical Domains (LDoms) and Solaris Containers, the potential for server consolidation is compelling.

Standard configurations of the Sun SPARC Enterprise T5440 include 2- and 4-chip systems at 1.2 GHz, and a 4-chip system at 1.4 GHz. All of these configurations come with 8 cores per …

Find out about Sun's new 4-chip UltraSPARC T2 Plus system direct from the source: Sun's engineers.

Sun today announced the 4-chip variant of its UltraSPARC T2 Plus system, the Sun SPARC Enterprise T5440. This new system is the big brother of the 2-chip Sun SPARC Enterprise T5140 and T5240 systems released in April 2008. Each UltraSPARC T2 Plus chip offers 8 hardware strands in each of 8 cores. With up to four UltraSPARC T2 Plus chips delivering a total of 32 cores and 256 hardware threads and up to 512Gbytes of memory in a compact 4U package, the T5440 raises the bar for server performance, price-performance, energy efficiency, and compactness. And with Logical Domains (LDoms) and Solaris Containers, the potential for server consolidation is compelling.

Standard configurations of the Sun SPARC Enterprise T5440 include 2- and 4-chip systems at 1.2 GHz, and a 4-chip system at 1.4 GHz. All of these configurations come with 8 cores per …

MySQL Certification had another great month in September. It was our biggest month with a MySQL Users Conference (where the cost of each exam is deeply discounted). A total of 159 exams were taken and that is a 10 percent increase.

Total certifications earned was another non-UC record with 68. That was made up of 14 Developers, 27 DBAs, 7 Cluster DBAs, and 20 Associates. Congratulations to all those who worked so hard to earn these certifications.

Those of you wishing to take the exams in Japanese should keeping checking the website for a new, much improved translation that will be ready by the Japanese UC. Domo arigato, Toru-san!

And be sure to list your MySQL Certifications on your resumes and social networking pages. I had a long talk with an online recruiting company about the best way to find certified MySQL Developers and DBAa. The demand for individuals is there but writing the filters to sweep …

By Peter Gulutzan

A new addition inside the new “MySQL Online Backup” feature is encryption. Australian Senior Software Engineer Stewart Smith has already mentioned it a few months ago in his blog. There’s a preview that you can download on the online backup pages. It’s probably going to get architecture-reviewer approval next week. Probably it will be part of MySQL-6.0 source downloads soon. I extract some paragraphs from what I wrote in a non-public worklog task, WL#4271.

For BACKUP:
BACKUP DATABASE database_name TO ‘image-file-name’
ENCRYPTION_ALGORITHM = { AES | 3DES }
[ ENCRYPTION_KEYSIZE = { 128 | 192 | 256 } ]
PASSWORD = ‘password’;

Recently I had an interesting issue crop up. Due to an unfortunate migration incident in which involved master/master replication and not checking to see if replication was caught up, we ended up with an infinite replication loop of a number of SQL statements. awk helped immensely in the aftermath cleanup.

The basics of the replication infinite loop were (more…)

Last month I went to the Sun Microsystems / MySQL Developer Conference in Riga Latvia. Along with about 250 other people. The majority were MySQL developers, but as usual we had several attendees from MySQL support and administration, and a few non-MySQL people came to talk about Google, Drizzle, and PBXT. This was one of our annual “internal” conferences, so lots of stuff that we talked about in Riga will only be publicly announced around, say, the time of the next MySQL User Conference . I’ll just talk about the stuff that’s already leaked, and about my own involvements.

First let me give my impression of ‘morale’. It’s up, way up, since two years ago. I attribute this to two causes: removal of a problem, and a better team.

Huh? Haven’t I read non-MySQLers’ blogs about people leaving the team? …

I’m reading Intellectual Property and Open Source by Van Lindberg at the moment, and despite being about a relatively dry topic, I must admit that it’s a fascinating read.

Van Lindberg introduces the book by talking about the comments that end up on Slashdot.org, almost certainly prefixed by the expression IANAL (I Am Not A Lawyer) where people defend, discuss, and rip people up about the legalities of open source and the various licenses. Van Lindberg also talks about how he spends much of his time translating the contents of various legal documents into engineer speak and back again.

Despite being a proponent and long time user of free software and open source for the best part of my working life, I’ll admit to being completely ignorant of many of the issues. This isn’t through lack …