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
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
|
/**
* @file threadpool.h
* @author Nat Goodspeed
* @date 2021-10-21
* @brief ThreadPool configures a WorkQueue along with a pool of threads to
* service it.
*
* $LicenseInfo:firstyear=2021&license=viewerlgpl$
* Copyright (c) 2021, Linden Research, Inc.
* $/LicenseInfo$
*/
#if ! defined(LL_THREADPOOL_H)
#define LL_THREADPOOL_H
#include "workqueue.h"
#include <string>
#include <thread>
#include <utility> // std::pair
#include <vector>
namespace LL
{
class ThreadPool: public LLInstanceTracker<ThreadPool, std::string>
{
private:
using super = LLInstanceTracker<ThreadPool, std::string>;
public:
/**
* Pass ThreadPool a string name. This can be used to look up the
* relevant WorkQueue.
*
* The number of threads you pass sets the compile-time default. But
* if the user has overridden the LLSD map in the "ThreadPoolSizes"
* setting with a key matching this ThreadPool name, that setting
* overrides this parameter.
*
* Pass an explicit capacity to limit the size of the queue.
* Constraining the queue can cause a submitter to block. Do not
* constrain any ThreadPool accepting work from the main thread.
*/
ThreadPool(const std::string& name, size_t threads=1, size_t capacity=1024*1024);
virtual ~ThreadPool();
/**
* Launch the ThreadPool. Until this call, a constructed ThreadPool
* launches no threads. That permits coders to derive from ThreadPool,
* or store it as a member of some other class, but refrain from
* launching it until all other construction is complete.
*/
void start();
/**
* ThreadPool listens for application shutdown messages on the "LLApp"
* LLEventPump. Call close() to shut down this ThreadPool early.
*/
void close();
std::string getName() const { return mName; }
size_t getWidth() const { return mThreads.size(); }
/// obtain a non-const reference to the WorkQueue to post work to it
WorkQueue& getQueue() { return mQueue; }
/**
* Override run() if you need special processing. The default run()
* implementation simply calls WorkQueue::runUntilClose().
*/
virtual void run();
/**
* getConfiguredWidth() returns the setting, if any, for the specified
* ThreadPool name. Returns dft if the "ThreadPoolSizes" map does not
* contain the specified name.
*/
static
size_t getConfiguredWidth(const std::string& name, size_t dft=0);
/**
* This getWidth() returns the width of the instantiated ThreadPool
* with the specified name, if any. If no instance exists, returns its
* getConfiguredWidth() if any. If there's no instance and no relevant
* override, return dft. Presumably dft should match the threads
* parameter passed to the ThreadPool constructor call that will
* eventually instantiate the ThreadPool with that name.
*/
static
size_t getWidth(const std::string& name, size_t dft);
private:
void run(const std::string& name);
WorkQueue mQueue;
std::string mName;
size_t mThreadCount;
std::vector<std::pair<std::string, std::thread>> mThreads;
};
} // namespace LL
#endif /* ! defined(LL_THREADPOOL_H) */
|
