Simple ruby script to view Postgres stats

pg_top.rb

require 'yaml'
require 'terminal-table'

loop do
  # Get Running Processes
  rows = %w(pid client_addr state waiting query_start query)
  stats = `psql identified_production -t -c 'select #{rows.join(', ')} from pg_stat_activity order by state DESC'`
  stats = stats.split("\n")
  stats.map! { |s| s.split('|').map(&:strip) }

  data = {}
  stats.map do |s|
    pid = s[0] 
    data[pid] = {}
    rows.each_with_index { |row, idx|
      data[pid][row] = s[idx][0..128]
    }
  end


  # Get CPU Usage
  ps = `ps -o pid,pcpu #{data.keys.join(' ')}`.split("\n")[1..-1].map(&:split)
  ps.map do |(pid, pcpu)|
    data[pid]['pcpu'] = pcpu+'%'
  end


  table = Terminal::Table.new :headings => data.values.first.keys, :rows => data.values.map(&:values)
  system('clear')
  puts table
  sleep 1
end