Shell one-liner using Ruby to create a histogram from a log file.

command.sh

export COL=$COLUMNS ; grep '\[CatalogItem\] Retrieved' production.log | awk '{ print $6 $7 }' | ruby -ne 'BEGIN { puts ENV.inspect;$columns = ENV["COL"].to_i;  $all = Hash.new { |h,k| h[k] = 0 } }; a, b = $_.split("(").map(&:to_f); next if a < 1; $all[((b/a/100).floor)] += a.to_i; END { max_value = $all.values.max;  puts "\e[2J\e[f"; puts "Average request time".center($columns); print "\033[37m" ; puts "ms/req ±50ms".center($columns); print "\033[0m" ; puts ("─" * $columns); $all.keys.sort.each { |k| puts "#{(k * 100 + 50).to_s.rjust(6)}: \033[31m#{"▓" * ($all[k].to_f / max_value * ($columns - 8))}\033[0m"; }; puts "─" * $columns; print "\033[5m\033[35m" ; puts "(╯°□°）╯︵ ┻━┻ © Arjan & Ariejan".center($columns); print "\033[0m" }'

Also see the Ruby-less version using Awk.