Has Amazon EC2 become over subscribed?
http://alan.blog-city.com/has_amazon_ec2_become_over_subscribed.htm
One of our aw2.0 portfolio companies, has been a long term user of Amazon EC2 running a sizable 24×7 of core instances with a number of instances going up and down as scale demands it. Our monthly bill gets us the dubious honor of a first point of contact with an Amazon Account Manager (not that that has been much use). We’ve pushed the limits of many of their services and continue to do so.
After 3 years of production usage what we can tell you is this .. Amazon do have a breaking point.
Visual evidence of Amazon EC2 network issues
https://www.cloudkick.com/blog/2010/jan/12/visual-ec2-latency/
http://news.ycombinator.com/item?id=1048873
http://news.ycombinator.com/item?id=1048694
As my mother would say; “misery enjoys company”
http://alan.blog-city.com/amazon_ec2_latency_the_pretty_graphs.htm
Amazon: We Don’t Have Cloud Capacity Issues
PLEASE SAY IT AIN’T SO, CLOUD OVER-SUBSCRIPTION?
http://vuksan.com/blog/2009/12/04/cloud-cartography-load-co-residence-detection/
I was actually quite surprised at the magnitude of degradation. I’d say this may be even a more successful co-residence detection attack than network probing since you could generate legitimate HTTP traffic to a site of interest (or a node of interest), throw tons of load at it and see if you notice response degradation.
What Clouds Can Learn From Airlines
http://www.infoq.com/news/2010/01/ec2-oversubscribed
There have been various reports from the community of Amazon EC2 users, that their instances are suffering poor performance, as the result of high internal network latency. This has led to speculations that Amazon’s Cloud might be getting oversubscribed.
http://tech.slashdot.org/story/10/01/15/1350213/Amazon-EC2-May-Be-Experiencing-Growing-Pains
“Some developers using Amazon EC2 are wondering aloud whether the popularity of the cloud computing service is beginning to affect its performance. Amazon this week denied speculation that it was experiencing capacity problems after a veteran developer reported performance issues and suggested that EC2 might be oversubscribed. Meanwhile, a cloud monitoring service published charts showing increased latency on EC2 in recent weeks. The reports follow an incident over the holidays in which a DDoS on a DNS provider slowed Amazon’s retail and cloud operations.”
http://www.mail-archive.com/hbase-user@hadoop.apache.org/msg08293.html
I have observed “noisy neighbor” effects.
If you are using HBase EC2 scripts, which run HBase region servers on all of the slaves colocated with tasktrackers and user tasks, I do not recommend using other than c1.xlarge instances.
Our scripts use c1.medium instances for the separate Zookeeper quorum ensemble as they need fewer resources in terms of RAM but are still sensitive to io and cpu scheduling latencies.
