A lot of monitoring systems have a goal of end-to-end tracing, from “click to disk” or something similar. This is usually implemented by adding some kind of tracing information to requests. You can take a look at X-Trace or Zipkin for a couple of examples. The idea is that you can collect complete traces of the entire call tree a user request generates, even across services and through different subsystems, so a slow web page load can be blamed on an overutilized disk somewhere.

I was at a database conference recently where this topic came up, and someone mentioned “blaming” resource usage on any of a variety of things. An example was blaming all disk I/O operations on tenants in a multi-tenant SaaS service. (My ears perked up, because VividCortex is such a service.)

VividCortex doesn’t do end-to-end tracing and it’s not a goal for us. However, the conversation made me pause and reexamine how I made the decision to …

A lot of times I’ve found the need to create a “Shop” page that shows the root category as an anchor (with layered navigation, for example). There are also a couple questions floating around on Stackexchange about how to have root categories be shown like normal categories.

By default Magento won’t show the root category for reasons I’ve still not found out.

There are a lot of modules that have that functionality, like Amasty’s Improved Navigation. However, it turns out it’s also pretty easy to do yourself.

In the Mage_Catalog_CategoryController::_initCatagory (yes, it’s spelled wrong) there is the following check:

if (!Mage::helper('catalog/category')->canShow($category)) {
        return false;
}

The canShow method …

Hello! I have posted this entry on the MySQL Server team's blog:
Storing UUID Values in MySQL Tables

After seeing that several blogs discuss storage of UUID values into MySQL, and that this topic is recurrent on forums, I thought I would compile some sensible ideas I have seen, and also add a couple new ones.

Different techniques

Say we have a table of users, and each user has a UUID.…

It's Oracle OpenWorld time, and MySQL Cluster will be in San Francisco again along with the rest of the MySQL team. 

The session agenda is online, but can be tricky to navigate given the breadth of the conference, but it's possible to narrow down to those sessions in the MySQL track.

From a MySQL Cluster perspective, there two conference sessions from the Cluster development team, a Hands-On Lab from our Cluster Support team and most …

We were delighted to announce that ClusterControl now supports MaxScale, the intelligent database gateway from the MariaDB team. In this blog, we will show you how to deploy and manage MaxScale from ClusterControl. We previously blogged about MaxScale, read it if you’d like a quick overview and introduction. We also published a quick benchmark of HAProxy vs MaxScale.

How to install MaxScale from ClusterControl

Assume you have a Galera Cluster currently managed by ClusterControl. As next step you want to install MaxScale as load balancer. From the ClusterControl UI, go to …

With the recent media attention Volkswagen has gotten, a lot of folks are wondering, how could that happen? Aren’t there checks & balances? Join 32,000 others and follow Sean Hull on twitter @hullsean. Then I ran across this observation on Todd Hoff’s brilliant blog High Scalability Is what Volkswagen did really any different that what … Continue reading Are software benchmarks to blame for Volkswagens woes? →

I am fascinated. Maybe that should be enough, but I guess I have to write a bit more here because we are not on twitter.

I spent a few days to get know Go language, and now I am more than satisfied. I mean, all the project ideas which are floating in my head should be written in Go.

First of all, I have rewritten Mambo-collector to go (https://github.com/banyek/mambo) because I have faced some serious errors when I used it on CentOS 7 – I blame systemd -: If the process was running as root then after a few days of data collecting, killing that process was lead to restart the entire system, which is not a bug, it is a catastrophe. I tried to debug it several ways, but I am not sure where the problem is, it could be at the ‘loghandler’ redirection or any other place in python-daemon, or it is simply there is a buffer inside which overflows – I don’t really care, because mambo was just a proof of concept – what I used in …

The Severalnines team is pleased to announce the release of ClusterControl 1.2.11. 

This release contains key new features, such as support for MariaDB’s MaxScale, along with performance improvements and bug fixes. This is also our best release yet for Postgres users, as outlined below.  

Join us for a release webinar on Tuesday, October 27th 2015, during which we will discuss the new features of this release as well as demonstrate them live.

Highlights of ClusterControl 1.2.11 include:

• New for PostgreSQL
  • Deployment and Management of Postgres Replicated Setups
  • Customisable …

I’m quite pleased to announce that my pull request for Kubernetes which provides a 3-node Galera cluster for Kubernetes was merged last week. I gave a presentation at Percona Live 2015 in Santa Clara, CA back in April about this an had since modified it to use newer Kubernete’s functionality, particular now that Kubernetes services allow more than one port and Kubernetes requires several ports. Also, Skydns, which provides the ability to specify the name (vs. IP address) of each node’s service when building up the wsrep_cluster_address string as well as providing a cluster-wide service.

Tim St. Clair (Google) was quite through and very helpful in his review and the code and docuementation ended up being very complete. You can find it on Kubernetes’ source code repo:

…