Netuality

Understanding the impact of using virtualized servers instead of real ones is perhaps one of the most complex issues when migrating from a traditional configuration to a cloud-based setup. Especially because virtualized servers are created equal … but only on paper.

A Rackspace-funded “report” tries to find out the performance differences between Rackspace Cloud Servers and Amazon EC2. I guess the only conclusion we can get from their so-called report is that Cloud Server disk throughput is better than EC2’s. As the “CPU test” is a kernel compile which also stresses the disk, I don’t think we can reliably get any conclusion from these.

An intrepid commenter ran a CPU-only test (Geekbench) and found out that EC2 performs slightly better than Rackspace in terms of raw processor performance. The same commenter, affiliated with Cloud Harmony,  mentions that a simple hdparm test shows that Rackspace hdd has more than twice the throughput of EC2 hdd, at least in terms of buffered reads. Last but not least, don’t forget that for better disk performance Amazon recommends EBS instead of the VM disk.

We cannot reliably make an informed cloud vendor choice just using VM benchmarks. Ideally, you should benchmark your own app on each cloud infrastructure and choose the one which gives you the best user-facing performance, because at the end of the day this is what matters most. Sadly, today this means experimenting with sometimes wildly different APIs and provisioning models.

Call to arms for the annual ACM KDD Conference. KDD stands for Knowledge Discovery and Data Mining, so if you’re looking for some hardcore use cases and new algorithms to apply, this is definitely the place to be (Washington, July 25-28):

KDD-2010 will feature keynote presentations, oral paper presentations, poster sessions, workshops, tutorials, panels, exhibits, demonstrations, and the KDD Cup competition.

There’s rumor on the street that Amazon EC2 is over-subscribed. From the trenches it appears that their scalability is … well, duh … not infinite and elasticity is a tiny bit rigid:

Anyone that uses virtualized computing, whether it is in the cloud or in their own private setup (VMWare for example) knows you take a performance hit. These performance hits can be considerable, but on the whole, are tolerable and can be built into an architecture from the start.

The problems that we are starting to see from Amazon, are more than just the overhead of a virtualized environment. They are deep rooted scalability problems at their end that need to be addressed sooner rather than later.

My Adobe colleague Ricky Ho has posted some notes on Oracle’s Coherence (formerly Tangosol), a distributed Java cache rich in features. A great read especially if you want a technical intro to the product (code snippets and everything).

The acquisition of the day is Zimbra being bought by VMWare. Yahoo is selling Zimbra a loss, it seems. Analysts wonder what exactly is VMWare planning to do, well they’re probably going up the stack and working on providing their own cloud ecosystem and related services. “VMWare Applications”, soon?

Under the terms of the agreement, Yahoo can continue to use Zimbra technology in its communications services. VMWare’s interest in Zimbra is a bit of a mystery since VMWare focuses on selling virtualization technology; in the release, VMWare offers somewhat of an explanation saying that the purchase furthers its “mission of taking complexity out of the datacenter, desktop, application development and core IT services”