useful info from /proc/[pid]/smaps

memstats.rb

#!/usr/bin/env ruby

#------------------------------------------------------------------------------
# Aggregate Print useful information from /proc/[pid]/smaps
#
# pss  - Roughly the amount of memory that is "really" being used by the pid
# swap - Amount of swap this process is currently using
#
# Reference:
#  http://www.mjmwired.net/kernel/Documentation/filesystems/proc.txt#361
#
# Example:
#   # ./memstats.rb 4386
#   Process:             4386
#   Command Line:        /usr/bin/mongod -f /etc/mongo/mongod.conf
#   Memory Summary:
#     private_clean             107,132 kB
#     private_dirty           2,020,676 kB
#     pss                     2,127,860 kB
#     rss                     2,128,536 kB
#     shared_clean                  728 kB
#     shared_dirty                    0 kB
#     size                  149,281,668 kB
#     swap                    1,719,792 kB
#------------------------------------------------------------------------------

class Mapping
  FIELDS = %w[ size rss shared_clean shared_dirty private_clean private_dirty swap pss ]
  attr_reader :address_start
  attr_reader :address_end
  attr_reader :perms
  attr_reader :offset
  attr_reader :device_major
  attr_reader :device_minor
  attr_reader :inode
  attr_reader :region

  attr_accessor :size
  attr_accessor :rss
  attr_accessor :shared_clean
  attr_accessor :shared_dirty
  attr_accessor :private_dirty
  attr_accessor :private_clean
  attr_accessor :swap
  attr_accessor :pss

  def initialize( lines )

    FIELDS.each do |field|
      self.send("#{field}=", 0)
    end

    parse_first_line( lines.shift )
    lines.each do |l|
      parse_field_line(l)
    end
  end

  def parse_first_line( line )
    parts = line.strip.split
    @address_start, @address_end = parts[0].split("-")
    @perms = parts[1]
    @offset = parts[2]
    @device_major, @device_minor = parts[3].split(":")
    @inode = parts[4]
    @region = parts[5] || "anonymous"
  end

  def parse_field_line( line )
    parts = line.strip.split
    field = parts[0].downcase.sub(':','')
    value = Float(parts[1]).to_i
    self.send( "#{field}=", value )
  end
end

def consume_mapping( map_lines, totals )
  m = Mapping.new( map_lines )

  Mapping::FIELDS.each do |field|
    totals[field] += m.send( field )
  end
  return m
end

pid = Float(ARGV.shift).to_i
abort "pid required" unless pid
totals = Hash.new(0)
mappings = []

File.open( "/proc/#{pid}/smaps" ) do |smaps|

  map_lines = []

  loop do
    break if smaps.eof?
    line = smaps.readline.strip
    case line
    when /\w+:\s+/
      map_lines << line
    when /[0-9a-f]+:[0-9a-f]+\s+/
      if map_lines.size > 0 then
        mappings << consume_mapping( map_lines, totals )
      end
      map_lines.clear
      map_lines << line
    else
      break
    end
  end
end

# http://rubyforge.org/snippet/download.php?type=snippet&id=511
def format_number( n )
  n.to_s.gsub(/(\d)(?=\d{3}+(?:\.|$))(\d{3}\..*)?/,'\1,\2')
end

def get_commandline( pid )
  commandline = IO.read( "/proc/#{pid}/cmdline" ).split("\0")
  if commandline.first =~ /java$/ then
    loop { break if commandline.shift == "-jar" }
    return "[java] #{commandline.shift}"
  end
  return commandline.join(' ')
end


puts "#{"Process:".ljust(20)} #{pid}"
puts "#{"Command Line:".ljust(20)} #{get_commandline(pid)}"
puts "Memory Summary:"
totals.keys.sort.each do |k|
  puts "  #{k.ljust(20)} #{format_number( totals[k] ).rjust(12)} kB"
end

swapstats.rb

#!/usr/bin/env ruby

#------------------------------------------------------------------------------
# Print out the processes that have swapped out regions of memory.
#
# Reference:
#  http://www.mjmwired.net/kernel/Documentation/filesystems/proc.txt#361
#
# Example:
#  #./swapstats.rb | head -3
#  4386    1,719,792 kB /usr/bin/mongod -f /etc/mongo/mongod.conf
#  5579    1,156,320 kB [java] /var/lib/term/term_service/start.jar
#  1863      618,072 kB [java] /var/lib/savi/savi/start.jar
#------------------------------------------------------------------------------


def get_pids
  Dir.entries("/proc").grep(/^\d+$/)
end

def swap_total( pid )
  total = 0
  File.open( "/proc/#{pid}/smaps" ) do |f|
    f.each_line do |line|
      if line =~ /Swap:\s+(\d+)\s+/
        total += Float($1).to_i
      end
    end
  end
  return total
end

# http://rubyforge.org/snippet/download.php?type=snippet&id=511
def format_number( n )
  n.to_s.gsub(/(\d)(?=\d{3}+(?:\.|$))(\d{3}\..*)?/,'\1,\2')
end

def get_commandline( pid )
  commandline = IO.read( "/proc/#{pid}/cmdline" ).split("\0")
  if commandline.first =~ /java$/ then
    loop { break if commandline.shift == "-jar" }
    return "[java] #{commandline.shift}"
  end
  return commandline.join(' ')
end

class SwapInfo
  attr_reader :pid
  attr_reader :commandline
  attr_reader :swap
  def initialize( pid, commandline, swap )
    @pid = pid
    @commandline = commandline
    @swap = swap
  end
end

swaps = []

get_pids.each do |pid|
  begin
    swap = swap_total( pid )
    if swap > 0 then
      swaps << SwapInfo.new( pid, get_commandline( pid ), swap )
    end
  rescue => e
  end
end

swaps.sort_by { |s| s.swap }.reverse.each do |swap|
  puts "#{swap.pid.to_s.rjust(6)} #{format_number(swap.swap).rjust(12)} kB #{swap.commandline}"
end

I got a NoMethod error at https://gist.github.com/copiousfreetime/1366013#file-memstats-rb-L73

it should be

self.send( "#{field}=", value ) if respond_to? "#{field}="