Prevent infinite keys on long idle samples

kbrock · Jul 3, 2012 · a3ecaf0 · a3ecaf0
1 parent 0597f7f
commit a3ecaf0
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diff --git a/lib/metriks/exponentially_decaying_sample.rb b/lib/metriks/exponentially_decaying_sample.rb
@@ -39,6 +39,7 @@ def snapshot
     def update(value, timestamp = Time.now)
       @mutex.synchronize do
         priority = weight(timestamp - @start_time) / rand
+        priority = Float::MAX if priority.infinite?
         new_count = @count.update { |v| v + 1 }
 
         if priority.nan?

diff --git a/test/histogram_test.rb b/test/histogram_test.rb
@@ -185,4 +185,15 @@ def test_exponential_sample_snapshot_threaded
 
     assert_equal 49.5, snapshot.median
   end
+
+  def test_long_idle_sample
+    Time.stubs(:now).returns(Time.new(2000))
+    sample = Metriks::ExponentiallyDecayingSample.new(Metriks::Histogram::DEFAULT_SAMPLE_SIZE, Metriks::Histogram::DEFAULT_ALPHA)
+    Time.unstub(:now)
+    @histogram = Metriks::Histogram.new(sample)
+
+    @histogram.update(5)
+
+    assert_equal 5, @histogram.min
+  end
 end