The ec2info was never intuitive to run - needing to set the AWS
envinronment variables, cd'ing into tools/ec2info, and knowing
to invoke the command.
This PR makes it so we can run ec2info just by running
make ec2info
The command now also checks for the AWS environment variables being
set, and provides a useful error if they are not.
Previously, Nomad was using a hand-made lookup table for looking
up EC2 CPU performance characteristics (core count + speed = ticks).
This data was incomplete and incorrect depending on region. The AWS
API has the correct data but requires API keys to use (i.e. should not
be queried directly from Nomad).
This change introduces a lookup table generated by a small command line
tool in Nomad's tools module which uses the Amazon AWS API.
Running the tool requires AWS_* environment variables set.
$ # in nomad/tools/cpuinfo
$ go run .
Going forward, Nomad can incorporate regeneration of the lookup table
somewhere in the CI pipeline so that we remain up-to-date on the latest
offerings from EC2.
Fixes#7830
hashicorp-copywrite[bot]