Measure Redis latency from inside of Heroku Dyno

redis_latency.rb

# repalce REDIS_CONNECTION with your Redis instance
# 
# run this script in Rails console. 
# For example start Heroku Dyno with Rails console to measure the Redis latency from inside of the Heroku Dyno
#
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rtts = []
100.times do
  a = b = 0; a = ::Process.clock_gettime(::Process::CLOCK_MONOTONIC, :microsecond); REDIS_CONNECTION.ping; b = ::Process.clock_gettime(::Process::CLOCK_MONOTONIC, :microsecond); rtt = b - a;
  puts "#{rtt} microseconds"
  rtts << rtt
  sleep 0.1
end

puts "Average: #{rtts.sum / rtts.size.to_f}"