Re:Why I left Heroku, and notes on my new AWS setup
by jcampbell1 on Monday May 20, 2013 @05:00PM
(#5740008)
EBS is a slow turd. Running a database on EBS is running a database on network attached storage. I know tons of people do this, but I have no idea why. Provisioned IOPS will work, but it is expensive.
Local storage on a $5 Digital Ocean plan will do 2000 IOPS, where as that would cost $200/month with Amazon Provisioned IOPS. I know it is not an apples to apples comparison, but it is worth thinking about. Running a database on a local SSD is a good option for many people, and it is not an option that Amazon offers.
The thing is that for whatever reason, data wasn't being written to the EBS (the virtual hard disks for use with EC2 instances) and was instead being written to the "ephemeral storage", a really big local data store that every EC2 instance has that is basically a `/tmp` directory. If the server restarts, everything in the ephemeral storage is destroyed.