38a54df863
People keep tripping over the old copyrights and copy-pasting them to new files. Search and replace "Cloudius Systems" with "ScyllaDB". Message-Id: <1460013664-25966-1-git-send-email-penberg@scylladb.com>
57 lines
1.8 KiB
C++
57 lines
1.8 KiB
C++
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/*
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* Copyright (C) 2015 ScyllaDB
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*/
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/*
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* This file is part of Scylla.
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*
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* Scylla is free software: you can redistribute it and/or modify
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* it under the terms of the GNU Affero General Public License as published by
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* the Free Software Foundation, either version 3 of the License, or
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* (at your option) any later version.
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*
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* Scylla is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with Scylla. If not, see <http://www.gnu.org/licenses/>.
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*/
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#pragma once
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#include "core/sleep.hh"
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#include <chrono>
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// Implements retry policy that exponentially increases sleep time between retries.
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class exponential_backoff_retry {
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std::chrono::milliseconds _base_sleep_time;
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std::chrono::milliseconds _sleep_time;
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std::chrono::milliseconds _max_sleep_time;
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public:
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exponential_backoff_retry(std::chrono::milliseconds base_sleep_time, std::chrono::milliseconds max_sleep_time)
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: _base_sleep_time(std::min(base_sleep_time, max_sleep_time))
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, _sleep_time(_base_sleep_time)
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, _max_sleep_time(max_sleep_time) {}
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future<> retry() {
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auto old_sleep_time = _sleep_time;
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// calculating sleep time seconds for the next retry.
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_sleep_time = std::min(_sleep_time * 2, _max_sleep_time);
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return sleep(old_sleep_time);
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}
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// Return sleep time in seconds to be used for next retry.
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std::chrono::milliseconds sleep_time() const {
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return _sleep_time;
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}
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// Reset sleep time to base sleep time.
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void reset() {
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_sleep_time = _base_sleep_time;
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}
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};
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