12f1137355
Summary: Introduces and uses a SystemClock class to RocksDB. This class contains the time-related functions of an Env and these functions can be redirected from the Env to the SystemClock. Many of the places that used an Env (Timer, PerfStepTimer, RepeatableThread, RateLimiter, WriteController) for time-related functions have been changed to use SystemClock instead. There are likely more places that can be changed, but this is a start to show what can/should be done. Over time it would be nice to migrate most (if not all) of the uses of the time functions from the Env to the SystemClock. There are several Env classes that implement these functions. Most of these have not been converted yet to SystemClock implementations; that will come in a subsequent PR. It would be good to unify many of the Mock Timer implementations, so that they behave similarly and be tested similarly (some override Sleep, some use a MockSleep, etc). Additionally, this change will allow new methods to be introduced to the SystemClock (like https://github.com/facebook/rocksdb/issues/7101 WaitFor) in a consistent manner across a smaller number of classes. Pull Request resolved: https://github.com/facebook/rocksdb/pull/7858 Reviewed By: pdillinger Differential Revision: D26006406 Pulled By: mrambacher fbshipit-source-id: ed10a8abbdab7ff2e23d69d85bd25b3e7e899e90
117 lines
3.4 KiB
C++
117 lines
3.4 KiB
C++
// Copyright (c) 2011-present, Facebook, Inc. All rights reserved.
|
|
// This source code is licensed under both the GPLv2 (found in the
|
|
// COPYING file in the root directory) and Apache 2.0 License
|
|
// (found in the LICENSE.Apache file in the root directory).
|
|
//
|
|
// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
|
|
// Use of this source code is governed by a BSD-style license that can be
|
|
// found in the LICENSE file. See the AUTHORS file for names of contributors.
|
|
|
|
#pragma once
|
|
|
|
#include <algorithm>
|
|
#include <atomic>
|
|
#include <chrono>
|
|
#include <deque>
|
|
|
|
#include "port/port.h"
|
|
#include "rocksdb/env.h"
|
|
#include "rocksdb/rate_limiter.h"
|
|
#include "rocksdb/system_clock.h"
|
|
#include "util/mutexlock.h"
|
|
#include "util/random.h"
|
|
|
|
namespace ROCKSDB_NAMESPACE {
|
|
|
|
class GenericRateLimiter : public RateLimiter {
|
|
public:
|
|
GenericRateLimiter(int64_t refill_bytes, int64_t refill_period_us,
|
|
int32_t fairness, RateLimiter::Mode mode,
|
|
const std::shared_ptr<SystemClock>& clock,
|
|
bool auto_tuned);
|
|
|
|
virtual ~GenericRateLimiter();
|
|
|
|
// This API allows user to dynamically change rate limiter's bytes per second.
|
|
virtual void SetBytesPerSecond(int64_t bytes_per_second) override;
|
|
|
|
// Request for token to write bytes. If this request can not be satisfied,
|
|
// the call is blocked. Caller is responsible to make sure
|
|
// bytes <= GetSingleBurstBytes()
|
|
using RateLimiter::Request;
|
|
virtual void Request(const int64_t bytes, const Env::IOPriority pri,
|
|
Statistics* stats) override;
|
|
|
|
virtual int64_t GetSingleBurstBytes() const override {
|
|
return refill_bytes_per_period_.load(std::memory_order_relaxed);
|
|
}
|
|
|
|
virtual int64_t GetTotalBytesThrough(
|
|
const Env::IOPriority pri = Env::IO_TOTAL) const override {
|
|
MutexLock g(&request_mutex_);
|
|
if (pri == Env::IO_TOTAL) {
|
|
return total_bytes_through_[Env::IO_LOW] +
|
|
total_bytes_through_[Env::IO_HIGH];
|
|
}
|
|
return total_bytes_through_[pri];
|
|
}
|
|
|
|
virtual int64_t GetTotalRequests(
|
|
const Env::IOPriority pri = Env::IO_TOTAL) const override {
|
|
MutexLock g(&request_mutex_);
|
|
if (pri == Env::IO_TOTAL) {
|
|
return total_requests_[Env::IO_LOW] + total_requests_[Env::IO_HIGH];
|
|
}
|
|
return total_requests_[pri];
|
|
}
|
|
|
|
virtual int64_t GetBytesPerSecond() const override {
|
|
return rate_bytes_per_sec_;
|
|
}
|
|
|
|
private:
|
|
void Refill();
|
|
int64_t CalculateRefillBytesPerPeriod(int64_t rate_bytes_per_sec);
|
|
Status Tune();
|
|
|
|
uint64_t NowMicrosMonotonic(const std::shared_ptr<SystemClock>& clock) {
|
|
return clock->NowNanos() / std::milli::den;
|
|
}
|
|
|
|
// This mutex guard all internal states
|
|
mutable port::Mutex request_mutex_;
|
|
|
|
const int64_t kMinRefillBytesPerPeriod = 100;
|
|
|
|
const int64_t refill_period_us_;
|
|
|
|
int64_t rate_bytes_per_sec_;
|
|
// This variable can be changed dynamically.
|
|
std::atomic<int64_t> refill_bytes_per_period_;
|
|
std::shared_ptr<SystemClock> clock_;
|
|
|
|
bool stop_;
|
|
port::CondVar exit_cv_;
|
|
int32_t requests_to_wait_;
|
|
|
|
int64_t total_requests_[Env::IO_TOTAL];
|
|
int64_t total_bytes_through_[Env::IO_TOTAL];
|
|
int64_t available_bytes_;
|
|
int64_t next_refill_us_;
|
|
|
|
int32_t fairness_;
|
|
Random rnd_;
|
|
|
|
struct Req;
|
|
Req* leader_;
|
|
std::deque<Req*> queue_[Env::IO_TOTAL];
|
|
|
|
bool auto_tuned_;
|
|
int64_t num_drains_;
|
|
int64_t prev_num_drains_;
|
|
const int64_t max_bytes_per_sec_;
|
|
std::chrono::microseconds tuned_time_;
|
|
};
|
|
|
|
} // namespace ROCKSDB_NAMESPACE
|