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scylladb/utils/bounded_stats_deque.hh
2015-04-23 14:55:26 +08:00

69 lines
1.6 KiB
C++

/*
* 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.
*
* Modified by Cloudius Systems.
* Copyright 2015 Cloudius Systems.
*/
#pragma once
namespace utils {
#include <deque>
/**
* bounded threadsafe deque
*/
class bounded_stats_deque {
private:
std::deque<long> _deque;
long _sum = 0;
int _max_size;
public:
bounded_stats_deque(int size)
: _max_size(size) {
}
int size() {
return _deque.size();
}
void add(long i) {
if (size() >= _max_size) {
auto removed = _deque.front();
_deque.pop_front();
_sum -= removed;
}
_deque.push_back(i);
_sum += i;
}
long sum() {
return _sum;
}
double mean() {
return size() > 0 ? ((double) sum()) / size() : 0;
}
const std::deque<long>& deque() const {
return _deque;
}
};
}