The big cloud news of the day is Amazon’s announcement of Amazon RDS, a MySQL database in the cloud. There will be some interesting commentary over the next few days, particularly the timing of the announcement so close to Microsoft’s PDC, which is where Windows Azure and SQL Azure are to be officially launched. Apart from the timing and pricing of the AWS announcement, there are two items that I find interesting.
Firstly, AWS now has a ‘High-Memory Quadruple Extra Large Instance’ EC2 option, which is a machine with 68GB of memory and 8 virtual cores. These are quite beefy machines and will have an impact on how systems are built for EC2. The baseline for ‘commodity server’, which is an important concept in the cloud, has moved upwards (as it always will) and us more interesting options for implementations.
Secondly, Amazon RDS seems to be a single node MySQL database and Amazon has forgone the high availability approach of Microsoft’s SQL Azure (which keeps three running instances in sync) in favour of a more traditional looking database that can be any size you want. Amazon RDS allows the creation of a 1TB database, 100x bigger than the 10GB limit of SQL Azure. The 10GB limit of SQL Azure is considered one of the barriers to entry (resulting in various discussions about sharding) and exists as a result of the three node architecture of SQL Azure that has to effectively mirror each database instance with two others – not something that can be easily done with a 1TB database. The SQL Azure architecture is also largely the culprit behind the features that have been cut from SQL 2008 to make it work on SQL Azure. Amazon RDS has taken a different, and probably technically simpler, approach by providing a plain ol’ MySQL database in the cloud that runs the same as other MySQL installations and is accessible using the same tools.
So customers that choose to have high availability out of the box can buy SQL Azure and put up with the limitations. Those customers that just want a big enough and less complex (and feature rich) database in the cloud can choose Amazon RDS.
Amazon is the market leader in the cloud and their offering is compelling. While SQL Azure is probably technically better, it is a difficult sell – database size and available memory are easier concepts for customers to understand than high availability.
It will be interesting to see how Microsoft positions and sells SQL Azure against Amazon RDS.
Simon Munro
@simonmunro