1 files changed, 11 insertions, 0 deletions
diff --git a/util/histogram.cc b/util/histogram.cc
index c5178ef..12ec3cf 100644
--- a/util/histogram.cc
+++ b/util/histogram.cc
@@ -55,6 +55,17 @@ void Histogram::Add(double value) {
   sum_squares_ += (value * value);
 }
 
+void Histogram::Merge(const Histogram& other) {
+  if (other.min_ < min_) min_ = other.min_;
+  if (other.max_ > max_) max_ = other.max_;
+  num_ += other.num_;
+  sum_ += other.sum_;
+  sum_squares_ += other.sum_squares_;
+  for (int b = 0; b < kNumBuckets; b++) {
+    buckets_[b] += other.buckets_[b];
+  }
+}
+
 double Histogram::Median() const {
   return Percentile(50.0);
 }