1<html> 2<head> 3<meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> 4<title>thread_pool</title> 5<link rel="stylesheet" href="../../../../doc/src/boostbook.css" type="text/css"> 6<meta name="generator" content="DocBook XSL Stylesheets V1.79.1"> 7<link rel="home" href="../../boost_asio.html" title="Boost.Asio"> 8<link rel="up" href="../reference.html" title="Reference"> 9<link rel="prev" href="this_coro__executor_t/executor_t.html" title="this_coro::executor_t::executor_t"> 10<link rel="next" href="thread_pool/add_service.html" title="thread_pool::add_service"> 11</head> 12<body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"> 13<table cellpadding="2" width="100%"><tr> 14<td valign="top"><img alt="Boost C++ Libraries" width="277" height="86" src="../../../../boost.png"></td> 15<td align="center"><a href="../../../../index.html">Home</a></td> 16<td align="center"><a href="../../../../libs/libraries.htm">Libraries</a></td> 17<td 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thread pool. 31 </p> 32<pre class="programlisting">class thread_pool : 33 public execution_context 34</pre> 35<h5> 36<a name="boost_asio.reference.thread_pool.h0"></a> 37 <span class="phrase"><a name="boost_asio.reference.thread_pool.types"></a></span><a class="link" href="thread_pool.html#boost_asio.reference.thread_pool.types">Types</a> 38 </h5> 39<div class="informaltable"><table class="table"> 40<colgroup> 41<col> 42<col> 43</colgroup> 44<thead><tr> 45<th> 46 <p> 47 Name 48 </p> 49 </th> 50<th> 51 <p> 52 Description 53 </p> 54 </th> 55</tr></thead> 56<tbody> 57<tr> 58<td> 59 <p> 60 <a class="link" href="thread_pool__basic_executor_type.html" title="thread_pool::basic_executor_type"><span class="bold"><strong>basic_executor_type</strong></span></a> 61 </p> 62 </td> 63<td> 64 <p> 65 Executor implementation type used to submit functions to a thread 66 pool. 67 </p> 68 </td> 69</tr> 70<tr> 71<td> 72 <p> 73 <a class="link" href="thread_pool/executor_type.html" title="thread_pool::executor_type"><span class="bold"><strong>executor_type</strong></span></a> 74 </p> 75 </td> 76<td> 77 <p> 78 Executor used to submit functions to a thread pool. 79 </p> 80 </td> 81</tr> 82<tr> 83<td> 84 <p> 85 <a class="link" href="thread_pool/fork_event.html" title="thread_pool::fork_event"><span class="bold"><strong>fork_event</strong></span></a> 86 </p> 87 </td> 88<td> 89 <p> 90 Fork-related event notifications. 91 </p> 92 </td> 93</tr> 94<tr> 95<td> 96 <p> 97 <a class="link" href="thread_pool/scheduler_type.html" title="thread_pool::scheduler_type"><span class="bold"><strong>scheduler_type</strong></span></a> 98 </p> 99 </td> 100<td> 101 <p> 102 Scheduler used to schedule receivers on a thread pool. 103 </p> 104 </td> 105</tr> 106</tbody> 107</table></div> 108<h5> 109<a name="boost_asio.reference.thread_pool.h1"></a> 110 <span class="phrase"><a name="boost_asio.reference.thread_pool.member_functions"></a></span><a class="link" href="thread_pool.html#boost_asio.reference.thread_pool.member_functions">Member 111 Functions</a> 112 </h5> 113<div class="informaltable"><table class="table"> 114<colgroup> 115<col> 116<col> 117</colgroup> 118<thead><tr> 119<th> 120 <p> 121 Name 122 </p> 123 </th> 124<th> 125 <p> 126 Description 127 </p> 128 </th> 129</tr></thead> 130<tbody> 131<tr> 132<td> 133 <p> 134 <a class="link" href="thread_pool/attach.html" title="thread_pool::attach"><span class="bold"><strong>attach</strong></span></a> 135 </p> 136 </td> 137<td> 138 <p> 139 Attaches the current thread to the pool. 140 </p> 141 </td> 142</tr> 143<tr> 144<td> 145 <p> 146 <a class="link" href="thread_pool/executor.html" title="thread_pool::executor"><span class="bold"><strong>executor</strong></span></a> 147 </p> 148 </td> 149<td> 150 <p> 151 Obtains the executor associated with the pool. 152 </p> 153 </td> 154</tr> 155<tr> 156<td> 157 <p> 158 <a class="link" href="thread_pool/get_executor.html" title="thread_pool::get_executor"><span class="bold"><strong>get_executor</strong></span></a> 159 </p> 160 </td> 161<td> 162 <p> 163 Obtains the executor associated with the pool. 164 </p> 165 </td> 166</tr> 167<tr> 168<td> 169 <p> 170 <a class="link" href="thread_pool/join.html" title="thread_pool::join"><span class="bold"><strong>join</strong></span></a> 171 </p> 172 </td> 173<td> 174 <p> 175 Joins the threads. 176 </p> 177 </td> 178</tr> 179<tr> 180<td> 181 <p> 182 <a class="link" href="thread_pool/notify_fork.html" title="thread_pool::notify_fork"><span class="bold"><strong>notify_fork</strong></span></a> 183 </p> 184 </td> 185<td> 186 <p> 187 Notify the execution_context of a fork-related event. 188 </p> 189 </td> 190</tr> 191<tr> 192<td> 193 <p> 194 <a class="link" href="thread_pool/scheduler.html" title="thread_pool::scheduler"><span class="bold"><strong>scheduler</strong></span></a> 195 </p> 196 </td> 197<td> 198 <p> 199 Obtains the scheduler associated with the pool. 200 </p> 201 </td> 202</tr> 203<tr> 204<td> 205 <p> 206 <a class="link" href="thread_pool/stop.html" title="thread_pool::stop"><span class="bold"><strong>stop</strong></span></a> 207 </p> 208 </td> 209<td> 210 <p> 211 Stops the threads. 212 </p> 213 </td> 214</tr> 215<tr> 216<td> 217 <p> 218 <a class="link" href="thread_pool/thread_pool.html" title="thread_pool::thread_pool"><span class="bold"><strong>thread_pool</strong></span></a> <span class="silver">[constructor]</span> 219 </p> 220 </td> 221<td> 222 <p> 223 Constructs a pool with an automatically determined number of threads. 224 <br> <span class="silver"> —</span><br> Constructs a pool with a specified number of threads. 225 </p> 226 </td> 227</tr> 228<tr> 229<td> 230 <p> 231 <a class="link" href="thread_pool/wait.html" title="thread_pool::wait"><span class="bold"><strong>wait</strong></span></a> 232 </p> 233 </td> 234<td> 235 <p> 236 Waits for threads to complete. 237 </p> 238 </td> 239</tr> 240<tr> 241<td> 242 <p> 243 <a class="link" href="thread_pool/_thread_pool.html" title="thread_pool::~thread_pool"><span class="bold"><strong>~thread_pool</strong></span></a> <span class="silver">[destructor]</span> 244 </p> 245 </td> 246<td> 247 <p> 248 Destructor. 249 </p> 250 </td> 251</tr> 252</tbody> 253</table></div> 254<h5> 255<a name="boost_asio.reference.thread_pool.h2"></a> 256 <span class="phrase"><a name="boost_asio.reference.thread_pool.protected_member_functions"></a></span><a class="link" href="thread_pool.html#boost_asio.reference.thread_pool.protected_member_functions">Protected 257 Member Functions</a> 258 </h5> 259<div class="informaltable"><table class="table"> 260<colgroup> 261<col> 262<col> 263</colgroup> 264<thead><tr> 265<th> 266 <p> 267 Name 268 </p> 269 </th> 270<th> 271 <p> 272 Description 273 </p> 274 </th> 275</tr></thead> 276<tbody> 277<tr> 278<td> 279 <p> 280 <a class="link" href="thread_pool/destroy.html" title="thread_pool::destroy"><span class="bold"><strong>destroy</strong></span></a> 281 </p> 282 </td> 283<td> 284 <p> 285 Destroys all services in the context. 286 </p> 287 </td> 288</tr> 289<tr> 290<td> 291 <p> 292 <a class="link" href="thread_pool/shutdown.html" title="thread_pool::shutdown"><span class="bold"><strong>shutdown</strong></span></a> 293 </p> 294 </td> 295<td> 296 <p> 297 Shuts down all services in the context. 298 </p> 299 </td> 300</tr> 301</tbody> 302</table></div> 303<h5> 304<a name="boost_asio.reference.thread_pool.h3"></a> 305 <span class="phrase"><a name="boost_asio.reference.thread_pool.friends"></a></span><a class="link" href="thread_pool.html#boost_asio.reference.thread_pool.friends">Friends</a> 306 </h5> 307<div class="informaltable"><table class="table"> 308<colgroup> 309<col> 310<col> 311</colgroup> 312<thead><tr> 313<th> 314 <p> 315 Name 316 </p> 317 </th> 318<th> 319 <p> 320 Description 321 </p> 322 </th> 323</tr></thead> 324<tbody> 325<tr> 326<td> 327 <p> 328 <a class="link" href="thread_pool/add_service.html" title="thread_pool::add_service"><span class="bold"><strong>add_service</strong></span></a> 329 </p> 330 </td> 331<td> 332 <p> 333 (Deprecated: Use make_service().) Add a service object to the execution_context. 334 </p> 335 </td> 336</tr> 337<tr> 338<td> 339 <p> 340 <a class="link" href="thread_pool/has_service.html" title="thread_pool::has_service"><span class="bold"><strong>has_service</strong></span></a> 341 </p> 342 </td> 343<td> 344 <p> 345 Determine if an execution_context contains a specified service 346 type. 347 </p> 348 </td> 349</tr> 350<tr> 351<td> 352 <p> 353 <a class="link" href="thread_pool/make_service.html" title="thread_pool::make_service"><span class="bold"><strong>make_service</strong></span></a> 354 </p> 355 </td> 356<td> 357 <p> 358 Creates a service object and adds it to the execution_context. 359 </p> 360 </td> 361</tr> 362<tr> 363<td> 364 <p> 365 <a class="link" href="thread_pool/use_service.html" title="thread_pool::use_service"><span class="bold"><strong>use_service</strong></span></a> 366 </p> 367 </td> 368<td> 369 <p> 370 Obtain the service object corresponding to the given type. 371 </p> 372 </td> 373</tr> 374</tbody> 375</table></div> 376<p> 377 The thread pool class is an execution context where functions are permitted 378 to run on one of a fixed number of threads. 379 </p> 380<h5> 381<a name="boost_asio.reference.thread_pool.h4"></a> 382 <span class="phrase"><a name="boost_asio.reference.thread_pool.submitting_tasks_to_the_pool"></a></span><a class="link" href="thread_pool.html#boost_asio.reference.thread_pool.submitting_tasks_to_the_pool">Submitting 383 tasks to the pool</a> 384 </h5> 385<p> 386 To submit functions to the thread pool, use the <a class="link" href="dispatch.html" title="dispatch"><code class="computeroutput">dispatch</code></a> 387 , <a class="link" href="post.html" title="post"><code class="computeroutput">post</code></a> or 388 <a class="link" href="defer.html" title="defer"><code class="computeroutput">defer</code></a> free 389 functions. 390 </p> 391<p> 392 For example: 393 </p> 394<pre class="programlisting">void my_task() 395{ 396 ... 397} 398 399... 400 401// Launch the pool with four threads. 402boost::asio::thread_pool pool(4); 403 404// Submit a function to the pool. 405boost::asio::post(pool, my_task); 406 407// Submit a lambda object to the pool. 408boost::asio::post(pool, 409 []() 410 { 411 ... 412 }); 413 414// Wait for all tasks in the pool to complete. 415pool.join(); 416</pre> 417<h5> 418<a name="boost_asio.reference.thread_pool.h5"></a> 419 <span class="phrase"><a name="boost_asio.reference.thread_pool.requirements"></a></span><a class="link" href="thread_pool.html#boost_asio.reference.thread_pool.requirements">Requirements</a> 420 </h5> 421<p> 422 <span class="emphasis"><em>Header: </em></span><code class="literal">boost/asio/thread_pool.hpp</code> 423 </p> 424<p> 425 <span class="emphasis"><em>Convenience header: </em></span><code class="literal">boost/asio.hpp</code> 426 </p> 427</div> 428<table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr> 429<td align="left"></td> 430<td align="right"><div class="copyright-footer">Copyright © 2003-2020 Christopher M. 431 Kohlhoff<p> 432 Distributed under the Boost Software License, Version 1.0. (See accompanying 433 file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>) 434 </p> 435</div></td> 436</tr></table> 437<hr> 438<div class="spirit-nav"> 439<a accesskey="p" href="this_coro__executor_t/executor_t.html"><img src="../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../reference.html"><img src="../../../../doc/src/images/up.png" alt="Up"></a><a accesskey="h" href="../../boost_asio.html"><img src="../../../../doc/src/images/home.png" alt="Home"></a><a accesskey="n" href="thread_pool/add_service.html"><img src="../../../../doc/src/images/next.png" alt="Next"></a> 440</div> 441</body> 442</html> 443
