On the road again - FOSSAsia

It has been a few busy months until now. I have moved from Italy to Thailand, and the move has been my first priority, keeping me from attending FOSDEM and interacting with social media. Now I start catching my breath, and looking around for new events to attend. But before I get into this, let’s make a few things clear:

• I am still working for Continuent. Actually, it’s because of my company flexibility that I could move to a different country (a different continent, 6 time zones away) without much trouble. Thanks, Continuent! (BTW: Continuent is hiring! )
• I am still involved with MySQL activities, events, and community matters. I just happen to be in a different time zone, where direct talk with people in Europe and …

I have just implemented MASTER_GTID_WAIT() in MariaDB 10.0. This can be used to give a very elegant solution to the problem of stale reads in replication read-scaleout, without incuring the overheads normally associated with synchronous replication techniques. This idea came up recently in a discussion with Stephane Varoqui, and is similar to the concept of Lamport logical clock described in this Wikipedia article.

I wanted to describe this, hoping to induce people to test and maybe start using this, as it is a simple but very neat idea, actually.

A very typical use of MariaDB/MySQL …

If you happen to work with personal data, chances are you are subject to SOX (Sarbanes-Oxley) whether you like it or not.

One of the worst aspects of this is that if you want to be able to analyse your data and you replicate out to another host, you have to find a way of anonymizing the information. There are of course lots of ways of doing this, but if you are replicating the data, why not anonymize it during the replication?

Of the many cool features in Tungsten Replicator, one of my favorites is filtering. This allows you to process the stream of changes that are coming from the data extracted from the master and perform operations on it. We use it a lot in the replicator for ignoring tables, schemas and columns, and for ensuring that we have the correct information within the THL.

Given this, let’s use it to anonymize the data as it is being replicated so that we don’t need to post-process it for analysis, and …

MySQL 5.6 has been GA for just over a year now. See MySQL 5.6.10 Release Notes.  Congratulations on your birthday! That is quite a long time. I was using it earlier in production because it worked and could do things that 5.5 could not do, but earlier versions were to use at your own risk, and indeed if prodded incorrectly would fall on the floor. That is fair enough because they were work in progress, yet if you poked them the right way they did a very good job.  Those dev versions have been long since upgraded which is good so they do not need quite as much care and attention.

So from where I see 5.6 it works very well. One big change that has made a large difference but which I think a lot of people may not really understand or use is the …

It's my pleasure to be presenting at SCaLE 12X on the subject of real-time data loading from MySQL to Hadoop.  This is the first public talk on work at Continuent that enables Tungsten Replicator to move transactions from MySQL to HDFS (Hadoop Distributed File System).  I will explain how replication to Hadoop works, how to set it up, and offer a few words on constructing views of MySQL data using tools like Hive.

As usual with replication everything we are doing on Hadoop replication is open source.  Builds and documentation will be publicly available …

At FOSDEM 2014 ProxySQL and MaxScale were both presented. Both are proxy that can help build sophisticated MariaDB/MySQL architectures. But currently what is the most used proxy with MySQL? It is HAproxy. HAproxy is a level 4 proxy that has no knowledge of the MySQL protocol. Being low level makes it very fast but it [...]

Last Wednesday, I spoke at the San Francisco MySQL Meetup on the topic of changes coming in MySQL 5.7 (and later).  We actually went through two different slide decks; the first on features being considered for deprecation in MySQL 5.7 (or later), and the second set providing a brief overview of the new features and benefits already introduced in MySQL 5.7 via the development milestone releases (DMRs) published to date.  A big thanks to the entire SF Meetup group, and in particular the organizers (Erin, Mike and Darren), for having me.  The event was streamed and recorded, and you can view the full presentation on YouTube.  The slide deck can be found here.

The discussion around proposed deprecation was good, and this blog serves to document my own notes about what …

The other day I was working on an issue where one of the slaves was showing unexpected lag. Interestingly with only the IO thread running the slave was doing significantly more IO as compared to the rate at which the IO thread was fetching the binary log events from the master.

I found this out by polling the SLAVE STATUS and monitoring the value of Read_Master_Log_Pos as it changed over time. Then compared it to the actual IO being done by the server using the pt-diskstats tool from the excellent Percona Toolkit. Note that, when doing this analysis, I had already stopped the slave SQL thread and made sure that there were no dirty InnoDB pages, otherwise my analysis would have …

Over the last few days, I integrated the MySQL 5.6 GTID version of the Percona Replication Manager (PRM) work of Frédéric Descamps, a colleague at Percona. The agent supports the GTID replication mode of MySQL 5.6 and if the master suffers a hard crash, it picks the slave having applied the highest transaction ID from the dead master. Given the nature of GTID-based replication, that causes all the other slaves to resync appropriately to their new master which is pretty cool and must yet be matched by the regular PRM agent.

For now, it is part of a separate agent, mysql_prm56, which may be integrated with the regular agent in the future. To use it, download the agent with the link above, the pacemaker configuration is similar to the one of the regular PRM agent. If you start from scratch, have a look …

PerconaLive 2014 program is published

After a few months of submissions and reviews, the program for PerconaLive MySQL Conference and Expo 2014 is published. The conference will be held in Santa Clara, from April 1 to 4, 2014.

Registration with early bird discount is available until February 2nd. If you plan to attend, this is probably the best time to act.

I will be presenting twice at the conference:

• MySQL Replication: Advanced features in all flavors it’s a 3 hours tutorial where I compare the …