Get some stats on RDS

get_rds_stats.rb

#!/usr/bin/env ruby

require 'aws-sdk'
@cw = AWS::CloudWatch::Client.new
@rds = AWS::RDS::Client.new

instances = @rds.describe_db_instances[:db_instances]
instances.map do |i|
  id = i[:db_instance_identifier]
  allocated_storage = i[:allocated_storage]

  free_storage_space = (@cw.get_metric_statistics( { namespace: "AWS/RDS",
                                    dimensions: [{ name: 'DBInstanceIdentifier', value: id }],
                                    period: 60,
                                    statistics: ["Maximum"],
                                    metric_name: "FreeStorageSpace",
                                    start_time: (Time.now - 60).iso8601,
                                    end_time: Time.now.iso8601 } )[:datapoints].first[:maximum]) / (1024**3)

  db_type = i[:engine]

  cpu = @cw.get_metric_statistics( { namespace: "AWS/RDS",
                                    dimensions: [{ name: 'DBInstanceIdentifier', value: id }],
                                    period: 60,
                                    statistics: ["Average"],
                                    metric_name: "CPUUtilization",
                                    start_time: (Time.now - 60*60*24).iso8601,
                                    end_time: Time.now.iso8601 } )[:datapoints].first[:average]

  queue = @cw.get_metric_statistics( { namespace: "AWS/RDS",
                                    dimensions: [{ name: 'DBInstanceIdentifier', value: id }],
                                    period: 60,
                                    statistics: ["Maximum"],
                                    metric_name: "DiskQueueDepth",
                                    start_time: (Time.now - 60*60*24).iso8601,
                                    end_time: Time.now.iso8601 } )[:datapoints].first[:maximum]



  disk_utilization = (allocated_storage-(free_storage_space))/allocated_storage

  puts "#{id},#{db_type},#{allocated_storage},#{free_storage_space},#{disk_utilization},#{cpu/100},#{queue}"


end