The author's takeaways include moving disks to io1. This is a bad bargain in most cases, and particularly bad in the ~500 IOPS range (which is what I'm seeing in the Grafana screenshot there). gp2 disks get 3 iops per gig "free", bursting up to 3k. (They don't burst after 1 tb, because your baseline performance is higher than the burst rate.) io1 is 25% more expensive per-gb, and you pay by the IOPS on top of that. A…
We recently upgraded one of our etcd clusters from v2 to v3 and it turned out that etcd v3 uses significantly more IOPS than v2, using EBS burst credit during periods with normal load. Our solution was to increase the EBS volume sizes from 16GB to 50GB (100 IOPS -> 150 IOPS [1]). Our costs went from $1.6 per volume to $5, instead of $11.75 for io1, for a comparable performance for this particular application.
1: http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/EBSVolume...