class MemoryProfiler

hook(klass, meth) click to toggle source

# File lib/memory_profiler.rb, line 80
def self.hook klass, meth
  klass.module_eval do
    old = meth.to_s.sub(%r%/, 'pct').sub(%r^/, 'old_')
    alias_method old, meth
    eval "def #{meth}(*args, &block)
      MemoryProfiler.log(self)
      #{old}(*args, &block)
    end"
  end
end

log(o) click to toggle source

# File lib/memory_profiler.rb, line 61
def self.log(o)
  loc = caller[1]
  unless @@locations.has_key? loc then
    @@locations[loc] = @@locations.size
  end
  loc = @@locations[loc]
  @@allocations[o.class][loc] += 1
end

profile(delay = 2, limit=10, output=$stderr) { || ... } click to toggle source

profile is a CLEAN, totally minimal memory profiler:

1 thread
2 hashes (curr, prev)
classes as keys
fixnums as values.

No extra memory required if I can help it. Keep it as simple as possible. The code at the link above is WAY to complex for such a simple task. It does use a sort_by, so that produces a bit extra junk… but that shouldn’t be more than an extra array and hash per iteration.

Just fire it up as ::profile or use it with a block of code:

MemoryProfiler.profile do
  # ...
end

# File lib/memory_profiler.rb, line 24
def self.profile(delay = 2, limit=10, output=$stderr)
  Thread.abort_on_exception = true
  totals = Hash.new(0)
  t = Thread.new do
    prev = Hash.new(0)
    curr = Hash.new(0)
    loop do
      curr.clear
      ObjectSpace.each_object do |o|
        curr[o.class] += 1
      end

      curr.each do |k,v|
        curr[k] -= prev[k]
      end

      puts
      curr.sort_by { |k,v| -v }.first(limit).each do |k,v|
        output.printf "%+5d: %s\n", v, k.name unless v == 0
      end

      prev.clear
      prev.update curr
      curr.each do |k,n| totals[k] += n end
      sleep delay
    end
  end
  if block_given? then
    yield
    t.exit
  end
  totals
end

report() click to toggle source

# File lib/memory_profiler.rb, line 91
def self.report
  keys = @@locations.invert

  puts
  puts "############################################################"
  puts "Spy Report:"

  @@allocations.each do |klass, locations|
    puts
    puts klass
    puts
    locations.sort_by { |k,v| -v }.first(10).each do |location, count|
      printf "%6d: %s\n", count, keys[location]
    end
  end
  p @@locations, @@allocations, keys if $DEBUG
end

spy_on(*klasses) click to toggle source

# File lib/memory_profiler.rb, line 70
def self.spy_on *klasses
  klasses.each do |klass|
    hook klass, :initialize
    if klass == String then
      hook klass, :%
      hook klass, :strip
    end
  end
end

Public Class Methods