diff options
Diffstat (limited to 'libtransport/src/hicn/transport/protocols/vegas_rto_estimator.cc')
-rwxr-xr-x | libtransport/src/hicn/transport/protocols/vegas_rto_estimator.cc | 57 |
1 files changed, 57 insertions, 0 deletions
diff --git a/libtransport/src/hicn/transport/protocols/vegas_rto_estimator.cc b/libtransport/src/hicn/transport/protocols/vegas_rto_estimator.cc new file mode 100755 index 000000000..f5f797bbe --- /dev/null +++ b/libtransport/src/hicn/transport/protocols/vegas_rto_estimator.cc @@ -0,0 +1,57 @@ +/* + * Copyright (c) 2017-2019 Cisco and/or its affiliates. + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at: + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ + +#include <hicn/transport/interfaces/socket_options_default_values.h> +#include <hicn/transport/protocols/vegas_rto_estimator.h> + +#include <algorithm> +#include <cmath> + +namespace transport { + +namespace protocol { + +using namespace interface; + +RtoEstimator::RtoEstimator(Duration min_rto) + : smoothed_rtt_(RtoEstimator::getInitialRtt().count()), + rtt_variation_(0), + first_measurement_(true), + last_rto_(min_rto.count()) {} + +void RtoEstimator::addMeasurement(Duration rtt) { + double duration = static_cast<double>(rtt.count()); + if (first_measurement_) { + smoothed_rtt_ = duration; + rtt_variation_ = duration / 2; + first_measurement_ = false; + } else { + rtt_variation_ = (1 - default_values::beta) * rtt_variation_ + + default_values::beta * std::abs(smoothed_rtt_ - duration); + smoothed_rtt_ = (1 - default_values::alpha) * smoothed_rtt_ + + default_values::alpha * duration; + } +} + +RtoEstimator::Duration RtoEstimator::computeRto() const { + double rto = smoothed_rtt_ + + std::max(double(default_values::clock_granularity.count()), + default_values::k* rtt_variation_); + return Duration(static_cast<Duration::rep>(rto)); +} + +} // end namespace protocol + +} // end namespace transport
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