Just wanted to follow up on this. We were never able to achieve throughput scaling in the cloud. We were able to verify that many of our cluster nodes and test servers were collocated on the same physical hardware (thanks Stu for the tip on the Rackspace REST API), and that performance on collocated nodes rose and fell in concert. Ultimately we moved to dedicated hardware and throughput scaled as expected with additional nodes.
Thanks for everyone's help on this. We had to move on in the interest of moving our project along, but I'd still be interested to see benchmarks from successful cloud installations. Maybe with the node routing in 0.7 and larger cluster sizes, the cloud might become a more viable option for highly available high read throughput applications. Best, -- Oren On Jul 20, 2010, at 3:18 PM, Peter Schuller wrote: >> (I'm hoping to have time to run my test on EC2 tonight; will see.) > > Well, I needed three c1.xlarge EC2 instances running py_stress to even > saturate more than one core on the c1.xlarge instance running a single > cassandra node (at roughly 21k reqs/second)... Depending on how > reliable vmstat/top is on EC2 to begin with. > > Would have to revisit this later if I'm to get any sensible numbers > that are even remotely trustworthy... > > -- > / Peter Schuller
