1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
|
/**
* Copyright (C) 2018-present MongoDB, Inc.
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the Server Side Public License, version 1,
* as published by MongoDB, Inc.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* Server Side Public License for more details.
*
* You should have received a copy of the Server Side Public License
* along with this program. If not, see
* <http://www.mongodb.com/licensing/server-side-public-license>.
*
* As a special exception, the copyright holders give permission to link the
* code of portions of this program with the OpenSSL library under certain
* conditions as described in each individual source file and distribute
* linked combinations including the program with the OpenSSL library. You
* must comply with the Server Side Public License in all respects for
* all of the code used other than as permitted herein. If you modify file(s)
* with this exception, you may extend this exception to your version of the
* file(s), but you are not obligated to do so. If you do not wish to do so,
* delete this exception statement from your version. If you delete this
* exception statement from all source files in the program, then also delete
* it in the license file.
*/
#pragma once
#include "mongo/util/tick_source.h"
namespace mongo {
/**
* Tick source based on platform specific clock ticks. Should be of reasonably high
* performance. The maximum span measurable by the counter and convertible to microseconds
* is about 10 trillion ticks. As long as there are fewer than 100 ticks per nanosecond,
* timer durations of 2.5 years will be supported. Since a typical tick duration will be
* under 10 per nanosecond, if not below 1 per nanosecond, this should not be an issue.
*/
class SystemTickSource final : public TickSource {
public:
TickSource::Tick getTicks() override;
TickSource::Tick getTicksPerSecond() override;
/**
* Gets the singleton instance of SystemTickSource. Should not be called before
* the global initializers are done.
*/
static SystemTickSource* get();
};
} // namespace mongo
|
