Merge pull request #803 from clemahieu/asio_threading

Holding more shared_ptrs instead of raw ptrs

examples/asio-sv.cc

@@ -36,12 +36,25 @@
 
 #include <iostream>
 #include <string>
+#include <thread>
 
 #include <nghttp2/asio_http2_server.h>
 
 using namespace nghttp2::asio_http2;
 using namespace nghttp2::asio_http2::server;
 
+namespace {
+void run_forever(boost::asio::io_service &io_service, size_t num_threads) {
+  std::vector<std::thread> ts;
+  for (size_t i = 0; i < num_threads; ++i) {
+    ts.emplace_back([&io_service]() { io_service.run(); });
+  }
+  for (auto &t : ts) {
+    t.join();
+  }
+}
+} // namespace
+
 int main(int argc, char *argv[]) {
   try {
     // Check command line arguments.
@@ -58,9 +71,9 @@ int main(int argc, char *argv[]) {
     std::string port = argv[2];
     std::size_t num_threads = std::stoi(argv[3]);
 
-    http2 server;
+    boost::asio::io_service io_service;
 
-    server.num_threads(num_threads);
+    http2 server(io_service);
 
     server.handle("/", [](const request &req, const response &res) {
       res.write_head(200, {{"foo", {"bar"}}});
@@ -136,11 +149,16 @@ int main(int argc, char *argv[]) {
       if (server.listen_and_serve(ec, tls, addr, port)) {
         std::cerr << "error: " << ec.message() << std::endl;
       }
+
+      run_forever(io_service, num_threads);
     } else {
       if (server.listen_and_serve(ec, addr, port)) {
         std::cerr << "error: " << ec.message() << std::endl;
       }
+
+      run_forever(io_service, num_threads);
     }
+
   } catch (std::exception &e) {
     std::cerr << "exception: " << e.what() << "\n";
   }

examples/asio-sv2.cc

@@ -43,12 +43,25 @@
 #endif // HAVE_FCNTL_H
 #include <iostream>
 #include <string>
+#include <thread>
 
 #include <nghttp2/asio_http2_server.h>
 
 using namespace nghttp2::asio_http2;
 using namespace nghttp2::asio_http2::server;
 
+namespace {
+void run_forever(boost::asio::io_service &io_service, size_t num_threads) {
+  std::vector<std::thread> ts;
+  for (size_t i = 0; i < num_threads; ++i) {
+    ts.emplace_back([&io_service]() { io_service.run(); });
+  }
+  for (auto &t : ts) {
+    t.join();
+  }
+}
+} // namespace
+
 int main(int argc, char *argv[]) {
   try {
     // Check command line arguments.
@@ -65,9 +78,9 @@ int main(int argc, char *argv[]) {
     std::size_t num_threads = std::stoi(argv[3]);
     std::string docroot = argv[4];
 
-    http2 server;
+    boost::asio::io_service io_service;
 
-    server.num_threads(num_threads);
+    http2 server(io_service);
 
     server.handle("/", [&docroot](const request &req, const response &res) {
       auto path = percent_decode(req.uri().path);
@@ -112,10 +125,14 @@ int main(int argc, char *argv[]) {
       if (server.listen_and_serve(ec, tls, addr, port)) {
         std::cerr << "error: " << ec.message() << std::endl;
       }
+
+      run_forever(io_service, num_threads);
     } else {
       if (server.listen_and_serve(ec, addr, port)) {
         std::cerr << "error: " << ec.message() << std::endl;
       }
+
+      run_forever(io_service, num_threads);
     }
   } catch (std::exception &e) {
     std::cerr << "exception: " << e.what() << "\n";

src/CMakeLists.txt

@@ -219,7 +219,6 @@ if(ENABLE_ASIO_LIB)
     ssl.cc
     timegm.c
     asio_common.cc
-    asio_io_service_pool.cc
     asio_server_http2.cc
     asio_server_http2_impl.cc
     asio_server.cc

src/Makefile.am

@@ -243,7 +243,6 @@ libnghttp2_asio_la_SOURCES = \
 	ssl_compat.h \
 	timegm.c timegm.h \
 	asio_common.cc asio_common.h \
-	asio_io_service_pool.cc asio_io_service_pool.h \
 	asio_server_http2.cc \
 	asio_server_http2_impl.cc asio_server_http2_impl.h \
 	asio_server.cc asio_server.h \

src/asio_client_session_impl.cc

@@ -69,17 +69,17 @@ void session_impl::start_resolve(const std::string &host,
                                  const std::string &service) {
   deadline_.expires_from_now(connect_timeout_);
 
-  auto self = this->shared_from_this();
+  auto self = shared_from_this();
 
   resolver_.async_resolve({host, service},
-                          [this, self](const boost::system::error_code &ec,
+                          [self](const boost::system::error_code &ec,
                                        tcp::resolver::iterator endpoint_it) {
                             if (ec) {
-                              not_connected(ec);
+                              self->not_connected(ec);
                               return;
                             }
 
-                            start_connect(endpoint_it);
+                            self->start_connect(endpoint_it);
                           });
 
   deadline_.async_wait(std::bind(&session_impl::handle_deadline, self));
@@ -597,38 +597,38 @@ void session_impl::do_read() {
 
   auto self = this->shared_from_this();
 
-  read_socket([this, self](const boost::system::error_code &ec,
+  read_socket([self](const boost::system::error_code &ec,
                            std::size_t bytes_transferred) {
     if (ec) {
-      if (!should_stop()) {
-        call_error_cb(ec);
+      if (!self->should_stop()) {
+        self->call_error_cb(ec);
       }
-      stop();
+      self->stop();
       return;
     }
 
     {
-      callback_guard cg(*this);
+      callback_guard cg(*self);
 
       auto rv =
-          nghttp2_session_mem_recv(session_, rb_.data(), bytes_transferred);
+          nghttp2_session_mem_recv(self->session_, self->rb_.data(), bytes_transferred);
 
       if (rv != static_cast<ssize_t>(bytes_transferred)) {
-        call_error_cb(make_error_code(
+        self->call_error_cb(make_error_code(
             static_cast<nghttp2_error>(rv < 0 ? rv : NGHTTP2_ERR_PROTO)));
-        stop();
+        self->stop();
         return;
       }
     }
 
-    do_write();
+    self->do_write();
 
-    if (should_stop()) {
-      stop();
+    if (self->should_stop()) {
+      self->stop();
       return;
     }
 
-    do_read();
+    self->do_read();
   });
 }
 
@@ -695,17 +695,17 @@ void session_impl::do_write() {
   auto self = this->shared_from_this();
 
   write_socket(
-      [this, self](const boost::system::error_code &ec, std::size_t n) {
+      [self](const boost::system::error_code &ec, std::size_t n) {
         if (ec) {
-          call_error_cb(ec);
-          stop();
+          self->call_error_cb(ec);
+          self->stop();
           return;
         }
 
-        wblen_ = 0;
-        writing_ = false;
+        self->wblen_ = 0;
+        self->writing_ = false;
 
-        do_write();
+        self->do_write();
       });
 }
 

src/asio_client_session_tcp_impl.cc

@@ -37,19 +37,20 @@ session_tcp_impl::session_tcp_impl(
 session_tcp_impl::~session_tcp_impl() {}
 
 void session_tcp_impl::start_connect(tcp::resolver::iterator endpoint_it) {
+  auto self = shared_from_this();
   boost::asio::async_connect(socket_, endpoint_it,
-                             [this](const boost::system::error_code &ec,
+                             [self](const boost::system::error_code &ec,
                                     tcp::resolver::iterator endpoint_it) {
-                               if (stopped()) {
+                               if (self->stopped()) {
                                  return;
                                }
 
                                if (ec) {
-                                 not_connected(ec);
+                                 self->not_connected(ec);
                                  return;
                                }
 
-                               connected(endpoint_it);
+                               self->connected(endpoint_it);
                              });
 }
 

src/asio_client_session_tls_impl.cc

@@ -43,37 +43,38 @@ session_tls_impl::session_tls_impl(
 session_tls_impl::~session_tls_impl() {}
 
 void session_tls_impl::start_connect(tcp::resolver::iterator endpoint_it) {
+  auto self = std::static_pointer_cast<session_tls_impl>(shared_from_this());
   boost::asio::async_connect(
-      socket(), endpoint_it, [this](const boost::system::error_code &ec,
+      socket(), endpoint_it, [self](const boost::system::error_code &ec,
                                     tcp::resolver::iterator endpoint_it) {
-        if (stopped()) {
+        if (self->stopped()) {
           return;
         }
 
         if (ec) {
-          not_connected(ec);
+          self->not_connected(ec);
           return;
         }
 
-        socket_.async_handshake(
+		self->socket_.async_handshake(
             boost::asio::ssl::stream_base::client,
-            [this, endpoint_it](const boost::system::error_code &ec) {
-              if (stopped()) {
+            [self, endpoint_it](const boost::system::error_code &ec) {
+              if (self->stopped()) {
                 return;
               }
 
               if (ec) {
-                not_connected(ec);
+                self->not_connected(ec);
                 return;
               }
 
-              if (!tls_h2_negotiated(socket_)) {
-                not_connected(make_error_code(
+              if (!tls_h2_negotiated(self->socket_)) {
+                self->not_connected(make_error_code(
                     NGHTTP2_ASIO_ERR_TLS_NO_APP_PROTO_NEGOTIATED));
                 return;
               }
 
-              connected(endpoint_it);
+              self->connected(endpoint_it);
             });
       });
 }

src/asio_io_service_pool.cc

@@ -1,102 +0,0 @@
-/*
- * nghttp2 - HTTP/2 C Library
- *
- * Copyright (c) 2014 Tatsuhiro Tsujikawa
- *
- * Permission is hereby granted, free of charge, to any person obtaining
- * a copy of this software and associated documentation files (the
- * "Software"), to deal in the Software without restriction, including
- * without limitation the rights to use, copy, modify, merge, publish,
- * distribute, sublicense, and/or sell copies of the Software, and to
- * permit persons to whom the Software is furnished to do so, subject to
- * the following conditions:
- *
- * The above copyright notice and this permission notice shall be
- * included in all copies or substantial portions of the Software.
- *
- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
- * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
- * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
- * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
- * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
- * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
- * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
- */
-// We wrote this code based on the original code which has the
-// following license:
-//
-// io_service_pool.cpp
-// ~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2013 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-#include "asio_io_service_pool.h"
-
-namespace nghttp2 {
-
-namespace asio_http2 {
-
-io_service_pool::io_service_pool(std::size_t pool_size) : next_io_service_(0) {
-  if (pool_size == 0) {
-    throw std::runtime_error("io_service_pool size is 0");
-  }
-
-  // Give all the io_services work to do so that their run() functions will not
-  // exit until they are explicitly stopped.
-  for (std::size_t i = 0; i < pool_size; ++i) {
-    auto io_service = std::make_shared<boost::asio::io_service>();
-    auto work = std::make_shared<boost::asio::io_service::work>(*io_service);
-    io_services_.push_back(io_service);
-    work_.push_back(work);
-  }
-}
-
-void io_service_pool::run(bool asynchronous) {
-  // Create a pool of threads to run all of the io_services.
-  for (std::size_t i = 0; i < io_services_.size(); ++i) {
-    futures_.push_back(std::async(std::launch::async,
-                                  (size_t(boost::asio::io_service::*)(void)) &
-                                      boost::asio::io_service::run,
-                                  io_services_[i]));
-  }
-
-  if (!asynchronous) {
-    join();
-  }
-}
-
-void io_service_pool::join() {
-  // Wait for all threads in the pool to exit.
-  for (auto &fut : futures_) {
-    fut.get();
-  }
-}
-
-void io_service_pool::stop() {
-  // Explicitly stop all io_services.
-  for (auto &iosv : io_services_) {
-    iosv->stop();
-  }
-}
-
-boost::asio::io_service &io_service_pool::get_io_service() {
-  // Use a round-robin scheme to choose the next io_service to use.
-  auto &io_service = *io_services_[next_io_service_];
-  ++next_io_service_;
-  if (next_io_service_ == io_services_.size()) {
-    next_io_service_ = 0;
-  }
-  return io_service;
-}
-
-const std::vector<std::shared_ptr<boost::asio::io_service>> &
-io_service_pool::io_services() const {
-  return io_services_;
-}
-
-} // namespace asio_http2
-
-} // namespace nghttp2

src/asio_io_service_pool.h

@@ -1,95 +0,0 @@
-/*
- * nghttp2 - HTTP/2 C Library
- *
- * Copyright (c) 2014 Tatsuhiro Tsujikawa
- *
- * Permission is hereby granted, free of charge, to any person obtaining
- * a copy of this software and associated documentation files (the
- * "Software"), to deal in the Software without restriction, including
- * without limitation the rights to use, copy, modify, merge, publish,
- * distribute, sublicense, and/or sell copies of the Software, and to
- * permit persons to whom the Software is furnished to do so, subject to
- * the following conditions:
- *
- * The above copyright notice and this permission notice shall be
- * included in all copies or substantial portions of the Software.
- *
- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
- * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
- * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
- * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
- * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
- * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
- * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
- */
-// We wrote this code based on the original code which has the
-// following license:
-//
-// io_service_pool.hpp
-// ~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2013 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_IO_SERVICE_POOL_H
-#define ASIO_IO_SERVICE_POOL_H
-
-#include "nghttp2_config.h"
-
-#include <vector>
-#include <memory>
-#include <future>
-
-#include <boost/noncopyable.hpp>
-#include <boost/thread.hpp>
-
-#include <nghttp2/asio_http2.h>
-
-namespace nghttp2 {
-
-namespace asio_http2 {
-
-/// A pool of io_service objects.
-class io_service_pool : private boost::noncopyable {
-public:
-  /// Construct the io_service pool.
-  explicit io_service_pool(std::size_t pool_size);
-
-  /// Run all io_service objects in the pool.
-  void run(bool asynchronous = false);
-
-  /// Stop all io_service objects in the pool.
-  void stop();
-
-  /// Join on all io_service objects in the pool.
-  void join();
-
-  /// Get an io_service to use.
-  boost::asio::io_service &get_io_service();
-
-  /// Get access to all io_service objects.
-  const std::vector<std::shared_ptr<boost::asio::io_service>> &
-  io_services() const;
-
-private:
-  /// The pool of io_services.
-  std::vector<std::shared_ptr<boost::asio::io_service>> io_services_;
-
-  /// The work that keeps the io_services running.
-  std::vector<std::shared_ptr<boost::asio::io_service::work>> work_;
-
-  /// The next io_service to use for a connection.
-  std::size_t next_io_service_;
-
-  /// Futures to all the io_service objects
-  std::vector<std::future<std::size_t>> futures_;
-};
-
-} // namespace asio_http2
-
-} // namespace nghttp2
-
-#endif // ASIO_IO_SERVICE_POOL_H

src/asio_server.cc

@@ -44,10 +44,10 @@ namespace nghttp2 {
 namespace asio_http2 {
 namespace server {
 
-server::server(std::size_t io_service_pool_size,
+server::server(boost::asio::io_service &service,
 			   const boost::posix_time::time_duration &tls_handshake_timeout,
                const boost::posix_time::time_duration &read_timeout)
-    : io_service_pool_(io_service_pool_size),
+    : service_(service),
 	  tls_handshake_timeout_(tls_handshake_timeout),
       read_timeout_(read_timeout) {}
 
@@ -70,8 +70,6 @@ server::listen_and_serve(boost::system::error_code &ec,
     }
   }
 
-  io_service_pool_.run(asynchronous);
-
   return ec;
 }
 
@@ -81,7 +79,7 @@ boost::system::error_code server::bind_and_listen(boost::system::error_code &ec,
                                                   int backlog) {
   // Open the acceptor with the option to reuse the address (i.e.
   // SO_REUSEADDR).
-  tcp::resolver resolver(io_service_pool_.get_io_service());
+  tcp::resolver resolver(service_);
   tcp::resolver::query query(address, port);
   auto it = resolver.resolve(query, ec);
   if (ec) {
@@ -90,7 +88,7 @@ boost::system::error_code server::bind_and_listen(boost::system::error_code &ec,
 
   for (; it != tcp::resolver::iterator(); ++it) {
     tcp::endpoint endpoint = *it;
-    auto acceptor = tcp::acceptor(io_service_pool_.get_io_service());
+    auto acceptor = tcp::acceptor(service_);
 
     if (acceptor.open(endpoint.protocol(), ec)) {
       continue;
@@ -126,7 +124,7 @@ void server::start_accept(boost::asio::ssl::context &tls_context,
                           tcp::acceptor &acceptor, serve_mux &mux) {
   auto new_connection = std::make_shared<connection<ssl_socket>>(
       mux, tls_handshake_timeout_, read_timeout_,
-      io_service_pool_.get_io_service(), tls_context);
+      service_, tls_context);
 
   acceptor.async_accept(
       new_connection->socket().lowest_layer(),
@@ -159,8 +157,7 @@ void server::start_accept(boost::asio::ssl::context &tls_context,
 
 void server::start_accept(tcp::acceptor &acceptor, serve_mux &mux) {
   auto new_connection = std::make_shared<connection<tcp::socket>>(
-      mux, tls_handshake_timeout_, read_timeout_,
-      io_service_pool_.get_io_service());
+      mux, tls_handshake_timeout_, read_timeout_, service_);
 
   acceptor.async_accept(
       new_connection->socket(), [this, &acceptor, &mux, new_connection](
@@ -177,19 +174,11 @@ void server::start_accept(tcp::acceptor &acceptor, serve_mux &mux) {
 }
 
 void server::stop() {
-  io_service_pool_.stop();
   for (auto &acceptor : acceptors_) {
     acceptor.close();
   }
 }
 
-void server::join() { io_service_pool_.join(); }
-
-const std::vector<std::shared_ptr<boost::asio::io_service>> &
-server::io_services() const {
-  return io_service_pool_.io_services();
-}
-
 } // namespace server
 } // namespace asio_http2
 } // namespace nghttp2

src/asio_server.h

@@ -44,11 +44,10 @@
 #include <memory>
 
 #include <boost/noncopyable.hpp>
+#include <boost/asio/io_service.hpp>
 
 #include <nghttp2/asio_http2_server.h>
 
-#include "asio_io_service_pool.h"
-
 namespace nghttp2 {
 
 namespace asio_http2 {
@@ -63,7 +62,7 @@ using ssl_socket = boost::asio::ssl::stream<tcp::socket>;
 
 class server : private boost::noncopyable {
 public:
-  explicit server(std::size_t io_service_pool_size,
+  explicit server(boost::asio::io_service &service,
                   const boost::posix_time::time_duration &tls_handshake_timeout,
                   const boost::posix_time::time_duration &read_timeout);
 
@@ -91,10 +90,7 @@ private:
                                             const std::string &address,
                                             const std::string &port,
                                             int backlog);
-
-  /// The pool of io_service objects used to perform asynchronous
-  /// operations.
-  io_service_pool io_service_pool_;
+  boost::asio::io_service &service_;
 
   /// Acceptor used to listen for incoming connections.
   std::vector<tcp::acceptor> acceptors_;

src/asio_server_http2.cc

@@ -36,7 +36,7 @@ namespace asio_http2 {
 
 namespace server {
 
-http2::http2() : impl_(make_unique<http2_impl>()) {}
+http2::http2(boost::asio::io_service &service) : impl_(make_unique<http2_impl>(service)) {}
 
 http2::~http2() {}
 
@@ -65,8 +65,6 @@ boost::system::error_code http2::listen_and_serve(
   return impl_->listen_and_serve(ec, &tls_context, address, port, asynchronous);
 }
 
-void http2::num_threads(size_t num_threads) { impl_->num_threads(num_threads); }
-
 void http2::backlog(int backlog) { impl_->backlog(backlog); }
 
 void http2::tls_handshake_timeout(const boost::posix_time::time_duration &t) {
@@ -83,13 +81,6 @@ bool http2::handle(std::string pattern, request_cb cb) {
 
 void http2::stop() { impl_->stop(); }
 
-void http2::join() { return impl_->join(); }
-
-const std::vector<std::shared_ptr<boost::asio::io_service>> &
-http2::io_services() const {
-  return impl_->io_services();
-}
-
 } // namespace server
 
 } // namespace asio_http2

src/asio_server_http2_impl.cc

@@ -37,8 +37,8 @@ namespace asio_http2 {
 
 namespace server {
 
-http2_impl::http2_impl()
-    : num_threads_(1),
+http2_impl::http2_impl(boost::asio::io_service &service)
+    : service_(service),
       backlog_(-1),
       tls_handshake_timeout_(boost::posix_time::seconds(60)),
       read_timeout_(boost::posix_time::seconds(60)) {}
@@ -47,13 +47,11 @@ boost::system::error_code http2_impl::listen_and_serve(
     boost::system::error_code &ec, boost::asio::ssl::context *tls_context,
     const std::string &address, const std::string &port, bool asynchronous) {
   server_.reset(
-      new server(num_threads_, tls_handshake_timeout_, read_timeout_));
+      new server(service_, tls_handshake_timeout_, read_timeout_));
   return server_->listen_and_serve(ec, tls_context, address, port, backlog_,
                                    mux_, asynchronous);
 }
 
-void http2_impl::num_threads(size_t num_threads) { num_threads_ = num_threads; }
-
 void http2_impl::backlog(int backlog) { backlog_ = backlog; }
 
 void http2_impl::tls_handshake_timeout(
@@ -71,13 +69,6 @@ bool http2_impl::handle(std::string pattern, request_cb cb) {
 
 void http2_impl::stop() { return server_->stop(); }
 
-void http2_impl::join() { return server_->join(); }
-
-const std::vector<std::shared_ptr<boost::asio::io_service>> &
-http2_impl::io_services() const {
-  return server_->io_services();
-}
-
 } // namespace server
 
 } // namespace asio_http2

src/asio_server_http2_impl.h

@@ -41,7 +41,7 @@ class server;
 
 class http2_impl {
 public:
-  http2_impl();
+  http2_impl(boost::asio::io_service &service);
   boost::system::error_code listen_and_serve(
       boost::system::error_code &ec, boost::asio::ssl::context *tls_context,
       const std::string &address, const std::string &port, bool asynchronous);
@@ -51,13 +51,10 @@ public:
   void read_timeout(const boost::posix_time::time_duration &t);
   bool handle(std::string pattern, request_cb cb);
   void stop();
-  void join();
-  const std::vector<std::shared_ptr<boost::asio::io_service>> &
-  io_services() const;
 
 private:
   std::unique_ptr<server> server_;
-  std::size_t num_threads_;
+  boost::asio::io_service &service_;
   int backlog_;
   serve_mux mux_;
   boost::posix_time::time_duration tls_handshake_timeout_;

src/includes/nghttp2/asio_http2_server.h

@@ -132,7 +132,7 @@ class http2_impl;
 
 class http2 {
 public:
-  http2();
+  http2(boost::asio::io_service &service);
   ~http2();
 
   http2(http2 &&other) noexcept;
@@ -190,10 +190,6 @@ public:
   // equivalent .- and ..-free URL.
   bool handle(std::string pattern, request_cb cb);
 
-  // Sets number of native threads to handle incoming HTTP request.
-  // It defaults to 1.
-  void num_threads(size_t num_threads);
-
   // Sets the maximum length to which the queue of pending
   // connections.
   void backlog(int backlog);
@@ -207,13 +203,6 @@ public:
   // Gracefully stop http2 server
   void stop();
 
-  // Join on http2 server and wait for it to fully stop
-  void join();
-
-  // Get access to the io_service objects.
-  const std::vector<std::shared_ptr<boost::asio::io_service>> &
-  io_services() const;
-
 private:
   std::unique_ptr<http2_impl> impl_;
 };