Semi-sync Replication is a plugin available for mysql which allows you to create more durable replication topologies.  For instance you can ensure that in the event of a master crash that at least one of your replicas has all transaction currently written to the master so that when you promote, you know you're not missing any data.

That's a huge simplification.

What's the downside?  Write speed.  If a transaction on your master have to wait until a replica acknowledges it has that transaction, then there is going to be some delay.  Not only that, but your network latency between the two points matters a lot.  If you want greater durability, the cost is performance.

It's important to note that the master doesn't wait until the replica actually runs the transaction on the …

Stephen O'Grady at RedMonk has launched a new Podcast called Hark. In his second episode, he and Agile programming guru Kent Beck have a thoughtful discussion around the ideas in O'Grady's book "The Software Paradox."  Even though software is "eating the world" and become more widespread and strategic, its economic value appears to be declining rapidly. Certainly, we've seen a shift in the …

I am potentially one of the least technical people in my generation. I’m 30 and I am afraid of my cellphone, my laptop, Netflix, the microwave…. Okay, afraid is maybe a strong word, but baffled by them at the very least.

In high school, while my classmates wrote most of their papers and assignments on the computer, I insisted on writing everything out by hand and only typed it out afterwards if absolutely required. It wasn’t that I had issues with typing – my mom who worked as an administrator for many years made sure that I learned to type from a very young age and I type quickly with a reasonable amount of accuracy. I just felt that writing by hand kept me more “connected” to the words I penned. Simply, my name is Sarah and I am a Luddite.

After high school I studied journalism for a couple of years and then entered the workforce into a number of different jobs, such as in sales and marketing and it became necessary …

A good portion of the startups I meet and advise want to use the newest, hottest technology to build something that’s cool, but not technologically groundbreaking. I have yet to meet a startup building a time machine, teleporter or quantum social network that would actually require some amazing new tech. They have awesome new ideas with down-to-earth technical requirements, so I kept wondering why they choose this shiny (and risky) new stuff when all they need is a good ol’ trustworthy database. I think it’s because many assume that building the latest and greatest needs the latest and greatest!

It turns out that’s only one of three bad reasons (traps) why people go for the shiny and new. Reason two is people mistakenly assume older stuff is slow, not feature rich or won’t scale. “MySQL is sluggish,” they say. “Java is slow,” I’ve heard. “Python won’t scale,” they claim. None of it’s true.

…

I helped a charity to rebuild a MySQL server and to restore a database with a lot of data of longblob type in the last two days. Fortunately there was a dump backup file for the database in question.

However, tables with longblob column(s) were not defined with “ROW_FORMAT=COMPRESSED”. I’d like to restore that database with row compression before inserting the data. Therefore I need to modify the dump sql file. The problem is that the file is 2.5 GB and the server only has 4 GB memory. So editing it is a challenge. Fortunately, Linux has sed to save the day. Don’t you love open source free software?

I am power Vi/Vim user, so I am familiar with sed and have used it in the past. But there are still a few things that I searched around for quick answers. So I’ll record noteworthy points here. I couldn’t remember how many times my own past blog entries helped me over the years. And I hope you’ll find this helpful too! …

The wild and crazy guys over at S&T Geotronics, James Sanderson and Marc Tessier, have decided to go full tilt with a Kickstarter version of their DIY Open Enigma Project.  For those who missed the fanfare last year, they were featured on Instructables showing how to build an Arduino-based encryption machine that works exactly like a WWII era Enigma.  You know, the thing that Alan friggin' Turing and his team at …

There is a good article over at Re-Code by ex-Microsoft VP Steven Sinofsky called "The Four Stages of Disruption".  It describes the evolution of products and markets through disruption, drawing from Sinofsky's own insights and also building on the work of Everett Rogers ("The Diffusion of Innovations") and Clayton Christensen ("The …

No one enjoys downtime. It reduces productivity and creates lost work, along with frustrated customers who depend on your services! Outages should not be considered business as usual. GenieDB grew from this frustration. Now with the launch of our new online Management Console, companies can experience the benefits of GenieDB’s geo-distributed, continuously available MySQL with just a few mouse clicks.

We’re excited to announce the availability of our simple and easy to use Management Console for automatic database administration. This includes backup processes, tuning and updates. With our globally distributed MySQL-as-a-service, our customers can launch MySQL database that remains available, and provide fast application response times – from anywhere in the world.

“Our management console makes it easy to take advantage of the benefits of GenieDB’s MySQL-as-a-Service,” said Cary Breese, CEO of GenieDB. …

Last year’s AWS re: Invent conference was described by many as one of the best technology conferences of 2012. This year, we’re pleased to be a sponsor and exhibitor at the event and will be heading over to Las Vegas from November 12-15.

Visit us at AWS re: Invent, booth #1205, and meet with the GenieDB team. We will be demonstrating our new globally distributed MySQL-as-a-Service, GenieDB’s scalable, DBaaS, which allows organizations of any size to build web-scale applications that gain the benefits of geographic database distribution. GenieDB offers continuous availability during regional cloud outages and better application response times for globally distributed users. 

“Unlike many other database solutions, GenieDB enables developers to meet the challenges of cloud environments without having to give up critical database …

I will change my host provider within a month. I’ve been using Midphase for several years and have decided to use Linode as my next virtual private service provider. I will move this site there in the next few weeks. This will be my first time moving a domain and I hope the transfer will be smooth without too much down time. After all, I know my readers worldwide are hanging on to every word I type and deserve a site that runs 24 by 7

Since I will have total control of this host, I decided to use Tengine, a great fork of the Nginx web/proxy server. Here is my note on how to compile and config Tengine on Debian/Ubuntu, and then setup WordPress. During my study and testing, the following sites are pretty helpful.

• Nginx installation on Ubuntu 12 …