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diff --git a/lib/mongrel/stats.rb b/lib/mongrel/stats.rb
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+# A very simple little class for doing some basic fast statistics sampling.
+# You feed it either samples of numeric data you want measured or you call
+# Stats.tick to get it to add a time delta between the last time you called it.
+# When you're done either call sum, sumsq, n, min, max, mean or sd to get 
+# the information.  The other option is to just call dump and see everything.
+#
+# It does all of this very fast and doesn't take up any memory since the samples
+# are not stored but instead all the values are calculated on the fly.
+class Stats
+  attr_reader :sum, :sumsq, :n, :min, :max
+
+  def initialize(name)
+    @name = name
+    reset
+  end
+
+  # Resets the internal counters so you can start sampling again.
+  def reset
+    @sum = 0.0
+    @sumsq = 0.0
+    @last_time = Time.new
+    @n = 0.0
+    @min = 0.0
+    @max = 0.0
+  end
+
+  # Adds a sampling to the calculations.
+  def sample(s)
+    @sum += s
+    @sumsq += s * s
+    if @n == 0
+      @min = @max = s
+    else
+      @min = s if @min > s
+      @max = s if @max < s
+    end
+    @n+=1
+  end
+
+  # Dump this Stats object with an optional additional message.
+  def dump(msg = "")
+    STDERR.puts "[#{@name}] #{msg} : SUM=#@sum, SUMSQ=#@sumsq, N=#@n, MEAN=#{mean}, SD=#{sd}, MIN=#@min, MAX=#@max"
+  end
+
+  # Calculates and returns the mean for the data passed so far.
+  def mean
+    @sum / @n
+  end
+
+  # Calculates the standard deviation of the data so far.
+  def sd
+    # (sqrt( ((s).sumsq - ( (s).sum * (s).sum / (s).n)) / ((s).n-1) ))
+    Math.sqrt( (@sumsq - ( @sum * @sum / @n)) / (@n-1) )
+  end
+
+
+  # Adds a time delta between now and the last time you called this.  This
+  # will give you the average time between two activities.
+  # 
+  # An example is:
+  #
+  #  t = Stats.new("do_stuff")
+  #  10000.times { do_stuff(); t.tick }
+  #  t.dump("time")
+  #
+  def tick
+    now = Time.now
+    sample(now - @last_time)
+    @last_time = now
+  end
+end