An article (Exploiting Hardware Heterogeneity within the Same Instance Type of Amazon EC2) linking to a paper from HotCloud ‘12 has some information about mixed instance types for Amazon EC2 machines. I found it interesting, so browsed through the article. Here are some observations I had when looking:
- “Furthermore, the high-memory instances use identical Intel X5550 processors” — Not true, from what I can tell. E5-2665 processors are used across at least us-east availability zones for all m2 instances sizes — m2.xlarge, m2.2xlarge, and m2.4xlarge. In fact, in several thousand instances spun up, it seems that these instances are used up to 70% of the time in one availability zone (though almost not at all in another.)
- The CPUBench test was done across 20 instances, but the Redis test appears to have only been done against one of each type, as far as I can read. I’m not totally convinced — given the variability in performance between node types — that this is entirely explained by instance differences — though given the CPUBench scores, it’s clear that some of the variablity could well be coming from that.
Anyway, I primarily wanted to comment on the high memory instances all using X5550s — since it’s clear that they don’t, at least not in US-East