folly/folly/logging/RateLimiter.h

/*
 * Copyright (c) Meta Platforms, Inc. and 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.
 */

#pragma once

#include <atomic>
#include <chrono>
#include <cstdint>
#include <type_traits>

#include <folly/Chrono.h>

namespace folly {
namespace logging {

/**
 * A rate limiter that can rate limit events to N events per M milliseconds.
 *
 * It is intended to be fast to check when messages are not being rate limited.
 * When messages are being rate limited it is slightly slower, as it has to
 * check the clock each time check() is called in this case.
 */
class IntervalRateLimiter { … };

} // namespace logging
} // namespace folly