mirror of
https://github.com/boostorg/asio.git
synced 2026-01-29 19:12:09 +00:00
260 lines
7.7 KiB
Plaintext
260 lines
7.7 KiB
Plaintext
[/
|
|
/ Copyright (c) 2003-2010 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)
|
|
/]
|
|
|
|
[section:implementation Platform-Specific Implementation Notes]
|
|
|
|
This section lists platform-specific implementation details, such as the
|
|
default demultiplexing mechanism, the number of threads created internally, and
|
|
when threads are created.
|
|
|
|
|
|
[heading Linux Kernel 2.4]
|
|
|
|
Demultiplexing mechanism:
|
|
|
|
* Uses `select` for demultiplexing. This means that the number of file
|
|
descriptors in the process cannot be permitted to exceed `FD_SETSIZE`.
|
|
|
|
Threads:
|
|
|
|
* Demultiplexing using `select` is performed in one of the threads that calls
|
|
`io_service::run()`, `io_service::run_one()`, `io_service::poll()` or
|
|
`io_service::poll_one()`.
|
|
|
|
* An additional thread per `io_service` is used to emulate asynchronous host
|
|
resolution. This thread is created on the first call to either
|
|
`ip::tcp::resolver::async_resolve()` or `ip::udp::resolver::async_resolve()`.
|
|
|
|
Scatter-Gather:
|
|
|
|
* At most `min(64,IOV_MAX)` buffers may be transferred in a single operation.
|
|
|
|
[heading Linux Kernel 2.6]
|
|
|
|
Demultiplexing mechanism:
|
|
|
|
* Uses `epoll` for demultiplexing.
|
|
|
|
Threads:
|
|
|
|
* Demultiplexing using `epoll` is performed in one of the threads that calls
|
|
`io_service::run()`, `io_service::run_one()`, `io_service::poll()` or
|
|
`io_service::poll_one()`.
|
|
|
|
* An additional thread per `io_service` is used to emulate asynchronous host
|
|
resolution. This thread is created on the first call to either
|
|
`ip::tcp::resolver::async_resolve()` or `ip::udp::resolver::async_resolve()`.
|
|
|
|
Scatter-Gather:
|
|
|
|
* At most `min(64,IOV_MAX)` buffers may be transferred in a single operation.
|
|
|
|
|
|
[heading Solaris]
|
|
|
|
Demultiplexing mechanism:
|
|
|
|
* Uses [^/dev/poll] for demultiplexing.
|
|
|
|
Threads:
|
|
|
|
* Demultiplexing using [^/dev/poll] is performed in one of the threads that
|
|
calls `io_service::run()`, `io_service::run_one()`, `io_service::poll()` or
|
|
`io_service::poll_one()`.
|
|
|
|
* An additional thread per `io_service` is used to emulate asynchronous host
|
|
resolution. This thread is created on the first call to either
|
|
`ip::tcp::resolver::async_resolve()` or `ip::udp::resolver::async_resolve()`.
|
|
|
|
Scatter-Gather:
|
|
|
|
* At most `min(64,IOV_MAX)` buffers may be transferred in a single operation.
|
|
|
|
|
|
[heading QNX Neutrino]
|
|
|
|
Demultiplexing mechanism:
|
|
|
|
* Uses `select` for demultiplexing. This means that the number of file
|
|
descriptors in the process cannot be permitted to exceed `FD_SETSIZE`.
|
|
|
|
Threads:
|
|
|
|
* Demultiplexing using `select` is performed in one of the threads that calls
|
|
`io_service::run()`, `io_service::run_one()`, `io_service::poll()` or
|
|
`io_service::poll_one()`.
|
|
|
|
* An additional thread per `io_service` is used to emulate asynchronous host
|
|
resolution. This thread is created on the first call to either
|
|
`ip::tcp::resolver::async_resolve()` or `ip::udp::resolver::async_resolve()`.
|
|
|
|
Scatter-Gather:
|
|
|
|
* At most `min(64,IOV_MAX)` buffers may be transferred in a single operation.
|
|
|
|
|
|
[heading Mac OS X]
|
|
|
|
Demultiplexing mechanism:
|
|
|
|
* Uses `kqueue` for demultiplexing.
|
|
|
|
Threads:
|
|
|
|
* Demultiplexing using `kqueue` is performed in one of the threads that calls
|
|
`io_service::run()`, `io_service::run_one()`, `io_service::poll()` or
|
|
`io_service::poll_one()`.
|
|
|
|
* An additional thread per `io_service` is used to emulate asynchronous host
|
|
resolution. This thread is created on the first call to either
|
|
`ip::tcp::resolver::async_resolve()` or `ip::udp::resolver::async_resolve()`.
|
|
|
|
Scatter-Gather:
|
|
|
|
* At most `min(64,IOV_MAX)` buffers may be transferred in a single operation.
|
|
|
|
|
|
[heading FreeBSD]
|
|
|
|
Demultiplexing mechanism:
|
|
|
|
* Uses `kqueue` for demultiplexing.
|
|
|
|
Threads:
|
|
|
|
* Demultiplexing using `kqueue` is performed in one of the threads that calls
|
|
`io_service::run()`, `io_service::run_one()`, `io_service::poll()` or
|
|
`io_service::poll_one()`.
|
|
|
|
* An additional thread per `io_service` is used to emulate asynchronous host
|
|
resolution. This thread is created on the first call to either
|
|
`ip::tcp::resolver::async_resolve()` or `ip::udp::resolver::async_resolve()`.
|
|
|
|
Scatter-Gather:
|
|
|
|
* At most `min(64,IOV_MAX)` buffers may be transferred in a single operation.
|
|
|
|
|
|
[heading AIX]
|
|
|
|
Demultiplexing mechanism:
|
|
|
|
* Uses `select` for demultiplexing. This means that the number of file
|
|
descriptors in the process cannot be permitted to exceed `FD_SETSIZE`.
|
|
|
|
Threads:
|
|
|
|
* Demultiplexing using `select` is performed in one of the threads that calls
|
|
`io_service::run()`, `io_service::run_one()`, `io_service::poll()` or
|
|
`io_service::poll_one()`.
|
|
|
|
* An additional thread per `io_service` is used to emulate asynchronous host
|
|
resolution. This thread is created on the first call to either
|
|
`ip::tcp::resolver::async_resolve()` or `ip::udp::resolver::async_resolve()`.
|
|
|
|
Scatter-Gather:
|
|
|
|
* At most `min(64,IOV_MAX)` buffers may be transferred in a single operation.
|
|
|
|
|
|
[heading HP-UX]
|
|
|
|
Demultiplexing mechanism:
|
|
|
|
* Uses `select` for demultiplexing. This means that the number of file
|
|
descriptors in the process cannot be permitted to exceed `FD_SETSIZE`.
|
|
|
|
Threads:
|
|
|
|
* Demultiplexing using `select` is performed in one of the threads that calls
|
|
`io_service::run()`, `io_service::run_one()`, `io_service::poll()` or
|
|
`io_service::poll_one()`.
|
|
|
|
* An additional thread per `io_service` is used to emulate asynchronous host
|
|
resolution. This thread is created on the first call to either
|
|
`ip::tcp::resolver::async_resolve()` or `ip::udp::resolver::async_resolve()`.
|
|
|
|
Scatter-Gather:
|
|
|
|
* At most `min(64,IOV_MAX)` buffers may be transferred in a single operation.
|
|
|
|
|
|
[heading Tru64]
|
|
|
|
Demultiplexing mechanism:
|
|
|
|
* Uses `select` for demultiplexing. This means that the number of file
|
|
descriptors in the process cannot be permitted to exceed `FD_SETSIZE`.
|
|
|
|
Threads:
|
|
|
|
* Demultiplexing using `select` is performed in one of the threads that calls
|
|
`io_service::run()`, `io_service::run_one()`, `io_service::poll()` or
|
|
`io_service::poll_one()`.
|
|
|
|
* An additional thread per `io_service` is used to emulate asynchronous host
|
|
resolution. This thread is created on the first call to either
|
|
`ip::tcp::resolver::async_resolve()` or `ip::udp::resolver::async_resolve()`.
|
|
|
|
Scatter-Gather:
|
|
|
|
* At most `min(64,IOV_MAX)` buffers may be transferred in a single operation.
|
|
|
|
|
|
[heading Windows 95, 98 and Me]
|
|
|
|
Demultiplexing mechanism:
|
|
|
|
* Uses `select` for demultiplexing.
|
|
|
|
Threads:
|
|
|
|
* Demultiplexing using `select` is performed in one of the threads that calls
|
|
`io_service::run()`, `io_service::run_one()`, `io_service::poll()` or
|
|
`io_service::poll_one()`.
|
|
|
|
* An additional thread per `io_service` is used to emulate asynchronous host
|
|
resolution. This thread is created on the first call to either
|
|
`ip::tcp::resolver::async_resolve()` or `ip::udp::resolver::async_resolve()`.
|
|
|
|
Scatter-Gather:
|
|
|
|
* For sockets, at most 16 buffers may be transferred in a single operation.
|
|
|
|
|
|
[heading Windows NT, 2000, XP, 2003 and Vista]
|
|
|
|
Demultiplexing mechanism:
|
|
|
|
* Uses overlapped I/O and I/O completion ports for all asynchronous socket
|
|
operations except for asynchronous connect.
|
|
|
|
* Uses `select` for emulating asynchronous connect.
|
|
|
|
Threads:
|
|
|
|
* Demultiplexing using I/O completion ports is performed in all threads that call
|
|
`io_service::run()`, `io_service::run_one()`, `io_service::poll()` or
|
|
`io_service::poll_one()`.
|
|
|
|
* An additional thread per `io_service` is used for the `select`
|
|
demultiplexing. This thread is created on the first call to `async_connect()`.
|
|
|
|
* An additional thread per `io_service` is used to emulate asynchronous host
|
|
resolution. This thread is created on the first call to either
|
|
`ip::tcp::resolver::async_resolve()` or `ip::udp::resolver::async_resolve()`.
|
|
|
|
Scatter-Gather:
|
|
|
|
* For sockets, at most 64 buffers may be transferred in a single operation.
|
|
|
|
* For stream-oriented handles, only one buffer may be transferred in a single
|
|
operation.
|
|
|
|
|
|
[endsect]
|