integrating the existing state of TON Storage / TON Payments / CPS Fift development branches

rldp2/Bbr.cpp

@@ -0,0 +1,62 @@
+#include "Bbr.h"
+
+#include "BdwStats.h"
+#include "RttStats.h"
+
+#include "td/utils/Random.h"
+
+namespace ton {
+namespace rldp2 {
+void Bbr::step(const RttStats &rtt_stats, const BdwStats &bdw_stats, td::uint64 in_flight, td::Timestamp now) {
+  rtt_min_ = rtt_stats.windowed_min_rtt;
+  bdw_max_ = bdw_stats.windowed_max_bdw;
+  if (bdw_max_ > bdw_peak_ * 1.25) {
+    bdw_peak_ = bdw_max_;
+    bdw_peak_at_round = rtt_stats.rtt_round;
+    //LOG(ERROR) << "NEW PEAK " << bdw_peak_ * 768;
+  }
+
+  if (state_ == State::Start && bdw_peak_at_round + 3 < rtt_stats.rtt_round) {
+    //LOG(ERROR) << "START -> DRAIN";
+    state_ = State::Drain;
+  }
+
+  if (state_ == State::Drain && (double)in_flight < bdw_max_ * rtt_min_) {
+    //LOG(ERROR) << "DRAIN -> BPROBE BDW";
+    state_ = State::ProbeBdw;
+    probe_bdw_cycle_ = td::Random::fast(1, 5);
+    probe_bdw_cycle_at_ = now;
+  }
+
+  if (state_ == State::ProbeBdw && td::Timestamp::in(rtt_stats.windowed_min_rtt, probe_bdw_cycle_at_).is_in_past(now)) {
+    probe_bdw_cycle_at_ = now;
+    probe_bdw_cycle_ = (probe_bdw_cycle_ + 1) % 6;
+    //LOG(ERROR) << "NEW PROBE BDW CYCLE";
+  }
+
+  //TODO: ProbeRtt state. Don't want to implenent now without proper tests
+}
+
+double Bbr::get_rate() const {
+  if (state_ == State::Start) {
+    return bdw_max_ * 2.8;
+  }
+  if (state_ == State::Drain) {
+    return bdw_max_ / 2.8;
+  }
+  if (state_ == State::ProbeBdw) {
+    constexpr double probe_bdw_gain[6] = {0.75, 1, 1, 1, 1, 1.25};
+    return probe_bdw_gain[probe_bdw_cycle_] * bdw_max_;
+  }
+  UNREACHABLE();
+}
+
+td::uint32 Bbr::get_window_size() const {
+  if (state_ == State::Start || state_ == State::Drain) {
+    return td::max(td::uint32(bdw_max_ * rtt_min_ * 2.8 + 1), 10u);
+  }
+  return td::max(td::uint32(bdw_max_ * rtt_min_ * 2 + 1), 10u);
+}
+
+}  // namespace rldp2
+}  // namespace ton