Obviously, cloud computing is not just a fancy trend anymore. Quite a few SaaS offerings are already built on platforms like Windows Azure. Others use Amazon’s EC2 to host their complete infrastructure or at least use it for additional resources to handle peak load or do “number-crunching”. Many also end up with a hybrid approach [...]

Like everybody else it took me a while to wrap my head around the BigTable concepts in Cassandra. The brain needs some time to accept that a column in Cassandra is really not the same as a column in our beloved RDBMS. After that I wrote the first Web Application and run into a pretty [...]

Last time I talked about the key differences between RDBMS and the most important NoSQL databases. The key reasons why NoSQL databases can scale the way they do is that they shard based on the entity. The „simplest“ form of NoSQL database shows this best, the distributed Key/Value Store. Last week I had the chance [...]

I have been working with performance sensitive applications for a long time now. As can be expected most of them have to use the database at one point or the other. So you inevitably end up having a connection pool. Now to make sure that your application is not suffering from waiting on connections you [...]

Are you running an eCommerce site that relies on 3rd Party Services such as Address-Validation, Credit Card Authorization or Mapping Services? Do you know how fast, reliable and accurate these service calls (free or charged) are for your web site? Do you know whether it has an impact on your end users in case one [...]

Most articles on the topic of NoSQL are around the theme of RDBMS vs. NoSQL. DBA’s are defending RDBMS by stating that NoSQL solutions are all dumb immature data stores without any standards. Many NoSQL proponents react with the argument that RDMBS does not scale and that today everybody needs to deal with huge amounts [...]

We often see request error rates as an indicator for SLA compliance. Reality however shows that this draws a wrong picture. Let’s start with an example. We had a meeting with a customer and were talking about their SLA and what it is based on. Like in many other cases the request error rate was [...]

There is no doubt that performance is important for your business. If you don’t agree you should check out what we and others think about the Performance Impact on Business or remember headlines like these: Target.com web site was down after promoting a new labels: Article on MSN Twitter was down and people complaining about [...]

I was looking at Cassandra, one of the major NoSQL solutions, and I was immediately impressed with its write speed even on my notebook. But I also noticed that it was very volatile in its response time, so I took a deeper look at it. First Cassandra Write Test I did the first write tests [...]

The ability to scale your environment on demand is one of the key advantages of a public cloud like Amazon EC2. Amazon provides a lot of functionality like the AutoScaling groups to make this easy. The one downside in my mind is that basing auto scaling on system metrics is a little naive and from [...]