Every couple of weeks or so I get marketing email from a Continuent competitor advertising a closed-source clone of MySQL. It is said to be pumped up on illegal substances and therefore the solution to all my problems.  I like this sort of spam because it makes it easier to track what the neighbors are up to.  However it does bring up a question.  Why are so many companies offering what amount to proprietary replacements of MySQL?  This does not mean alternative builds like Percona or MariaDB.  It means products like Clustrix, Schooner, or Xeround, which replace MySQL entirely, or like …

Cloudera raises $40m. Accel announces $100m fund. Rackspace takes OpenStack private. And more.

# Cloudera raised $40m in series D funding and announced a partnership with NetApp around its NetApp Open Solution for Hadoop.

# Accel Partners launched a $100m Big Data Fund to invest in Hadoop- and NoSQL-related vendors.

# Rackspace …

Working with replication, you come across many topologies, some of them sound and established, some of them less so, and some of them still in the realm of the hopeless wishes. I have been working with replication for almost 10 years now, and my wish list grew quite big during this time. In the last 12 months, though, while working at Continuent, some of the topologies that I wanted to work with have moved from the cloud of wishful thinking to the firm land of things that happen. My quest for star replication starts with the most common topology. One master, many slaves.

It looks like a star, with the rays extending from the master to the slaves. This is the basis of most of the replication going on mostly everywhere nowadays, and it has few surprises. Setting aside the …

Tungsten parallel apply on slaves, or parallel replication for short, has been available for about a year.   Until recently we did not have many formal benchmarks of its performance.  Fortunately the excellent Percona Live Conference in London accepted my talk on Tungsten parallel replication (slides available here), so Giuseppe Maxia and I finally allocated a block of time for systematic performance testing.

In a nutshell, the results were quite good. In the best cases Tungsten parallel apply out-performs single-threaded native replication by about 4.5 to 1.  Both Giuseppe and I have verified this using slightly different test methodologies, which …

Proof-of-concept Tungsten support for MongoDB arrived last May, when I posted about our hackathon effort to replicate from MySQL to MongoDB.  That code then lay fallow for a few months while we worked on other things like parallel replication, but the period of idleness has ended.  Earlier this week I checked in fixes to Tungsten Replicator to add one-line installation support for MongoDB slaves.

MySQL to MongoDB replication will be officially supported in the Tungsten Replicator 2.0.5 build, which will be available in a few weeks.  However, you can try out MySQL to MongoDB …

When I talked about the usability improvements of Tungsten Replicator, I did not mention the procedure for upgrading. I was reminded about it by a question in the TR mailing list, and since the question was very relevant, I updated the Tungsten Cookbook with some quick upgrading instructions. A quick upgrading procedure is as important as the installer. Since we release software quite often, either because we have scheduled features to release or because of bug fixes, users want to apply a new release to an existing installation without much fuss. You can do the upgrade with a very quick and painless procedure. Let's suppose that you have installed one Tungsten Replicator cluster using this command:

#
# using tungsten-replicator 2.0.4
# …

MySQL built-in replication includes a concept called relay slave, which allows you to create hierarchical database clusters. You can do the same thing with Tungsten, and this can be done in more than one way. Let's start with two distinct clusters. We can follow the recipes in the Tungsten Cookbook to install a master / slave cluster in three separate hosts and a …

One lesson learned in more than two decades working in this industry is that most of the IT professionals are impatient, want to achieve results immediately, and, most importantly, they don't read documentation. Much as the average geek is happy to answer many requests with a dismissive RTFM, the same geeks are not as diligent when it comes to learning about new or updated technologies. For this reason, there is a kind of documentation that is very much appreciated by busy and impatient professionals: cookbooks. And I am not talking about food. Geeks are not known for being cooks (1) and they like fast food. I am talking about collection of technical recipes, short articles where a problem is briefly stated, and a direct solution is shown. Working with Tungsten Replicator, I am constantly amazed at all the things you can do with it, and at the same time, I am amazed at how so few …