replacement for mysqladmin ext -ri10

mysql-var-stats.rb

# Equivalent to mysqladmin ext -ri10
#  - that is, if mysqladmin ext -ri10 works on your box
#  - in my case it didn't...
#
# Reports MySQL variable changes for a certain time period
#
# Running: ruby mysql-var-stats.rb interval

require 'rubygems'
require 'ruport'

trap("INT") { exit }
@prev = Hash.new(0)

while true
  curr = Hash.new(0)

  status = `mysqladmin ext`.split("\n")
  status.each do |line|
    var = line.split("|")
    next if var.size < 2
    curr[var[1].strip] = var[2].strip.to_i
  end

  report = Table(:column_names => ["Variable","Value", "Diff"])
  diff = curr.dup.delete_if { |k,v| @prev[k] == v }
  diff.each do |key, value|
    report << [key, value, curr[key]-@prev[key]]
  end

  puts report.to_s
  puts "\n\n"

  @prev = curr
  sleep ARGV[0].to_i
end

# Output:
#
# +----------------------------------------------------------+
# |             Variable              |   Value    |  Diff   |
# +----------------------------------------------------------+
# | Handler_read_next                 |     638727 |     224 |
# | Handler_read_rnd_next             |     117140 |     291 |
# | Innodb_data_fsyncs                |      77441 |      28 |
# ...
# | Innodb_pages_read                 |     205017 |      31 |
# | Innodb_buffer_pool_pages_dirty    |      81514 |     -83 |
# +----------------------------------------------------------+