ceph/src/jaegertracing/opentelemetry-cpp/third_party/prometheus-cpp/core/include/prometheus/detail/ckms_quantiles.h

   1 #pragma once
   2
   3 #include <array>
   4 #include <cstddef>
   5 #include <functional>
   6 #include <vector>
   7
   8 #include "prometheus/detail/core_export.h"
   9
  10 // IWYU pragma: private, include "prometheus/summary.h"
  11
  12 namespace prometheus {
  13 namespace detail {
  14
  15 class PROMETHEUS_CPP_CORE_EXPORT CKMSQuantiles {
  16  public:
  17   struct PROMETHEUS_CPP_CORE_EXPORT Quantile {
  18     Quantile(double quantile, double error);
  19
  20     double quantile;
  21     double error;
  22     double u;
  23     double v;
  24   };
  25
  26  private:
  27   struct Item {
  28     double value;
  29     int g;
  30     int delta;
  31
  32     Item(double value, int lower_delta, int delta);
  33   };
  34
  35  public:
  36   explicit CKMSQuantiles(const std::vector<Quantile>& quantiles);
  37
  38   void insert(double value);
  39   double get(double q);
  40   void reset();
  41
  42  private:
  43   double allowableError(int rank);
  44   bool insertBatch();
  45   void compress();
  46
  47  private:
  48   const std::reference_wrapper<const std::vector<Quantile>> quantiles_;
  49
  50   std::size_t count_;
  51   std::vector<Item> sample_;
  52   std::array<double, 500> buffer_;
  53   std::size_t buffer_count_;
  54 };
  55
  56 }  // namespace detail
  57 }  // namespace prometheus