gistfile1.rb

  class OobGCDisabled < OobGC
    def gc
      # do nothing
    end
  end
  
  # superclasses OobGCForInterval as a backup strategy if the max begins to fail
  class OobGCOnMaxMemory < OobGCForInterval
    attr_accessor :max_memory, :successful
    
    def initialize(app, max_memory, fallback_interval=5)
      super(app, fallback_interval)
      self.max_memory = max_memory.to_i
      self.successful = true
    end
    
    def should_gc?
      return true if (successful and (get_memory_usage > max_memory)) 
      
      # fallback to interval if this max memory strategy isn't working anymore
      super
    end
    
    def after_gc
      # check to see if we are running a successful stragegy still
      # if we are over the max after GC, then we can't use this strategy anymore
      # we still would need to call GC from time to time
      self.successful = get_memory_usage < max_memory
    end
    
    #copied from oink: http://github.com/marshally/oink/blob/master/lib/oink/rails/memory_usage_logger.rb
    def get_memory_usage
      if defined? WIN32OLE
        wmi = WIN32OLE.connect("winmgmts:root/cimv2")
        mem = 0
        query = "select * from Win32_Process where ProcessID = #{$$}"
        wmi.ExecQuery(query).each do |wproc|
          mem = wproc.WorkingSetSize
        end
        mem.to_i / 1000
      elsif proc_file = File.new("/proc/#{$$}/smaps") rescue nil
        proc_file.map do |line|
          size = line[/Size: *(\d+)/, 1] and size.to_i
        end.compact.sum
      elsif proc_file = File.new("/proc/#{$$}/status") rescue nil
        proc_file.map do |line|
          size = line[/VmSize:\s*(\d+)/, 1] and size.to_i
        end.compact.sum
      else
        `ps -o vsz= -p #{$$}`.to_i
      end
    end
    
  end