| // Licensed to the Apache Software Foundation (ASF) under one |
| // or more contributor license agreements. See the NOTICE file |
| // distributed with this work for additional information |
| // regarding copyright ownership. The ASF licenses this file |
| // to you 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. |
| #ifndef KUDU_UTIL_THROTTLER_H |
| #define KUDU_UTIL_THROTTLER_H |
| |
| #include <cstdint> |
| |
| #include "kudu/util/locks.h" |
| #include "kudu/util/monotime.h" |
| |
| namespace kudu { |
| |
| // A throttler to throttle both operation/s and IO byte/s. |
| class Throttler { |
| public: |
| // Refill period is 100ms. |
| enum { |
| kRefillPeriodMicros = 100000 |
| }; |
| |
| // Construct a throttler with max operation per second, max IO bytes per second |
| // and burst factor (burst_rate = rate * burst), burst rate means maximum |
| // throughput within one refill period. |
| // Set op_per_sec to 0 to disable operation throttling. |
| // Set byte_per_sec to 0 to disable IO bytes throttling. |
| Throttler(MonoTime now, uint64_t op_per_sec, uint64_t byte_per_sec, double burst_factor); |
| |
| // Throttle an "operation group" by taking 'op' operation tokens and 'byte' byte tokens. |
| // Return true if there are enough tokens, and operation is allowed. |
| // Return false if there are not enough tokens, and operation is throttled. |
| bool Take(MonoTime now, uint64_t op, uint64_t byte); |
| |
| private: |
| void Refill(MonoTime now); |
| |
| MonoTime next_refill_; |
| uint64_t op_refill_; |
| uint64_t op_token_; |
| uint64_t op_token_max_; |
| uint64_t byte_refill_; |
| uint64_t byte_token_; |
| uint64_t byte_token_max_; |
| simple_spinlock lock_; |
| }; |
| |
| } // namespace kudu |
| |
| #endif |