Databases
StackOverflow2013
Postsdbo
POUsing boost's SSL asio code, async_write_some hangs
 

Note that there are some explanatory texts on larger screens.

plurals
  1. POUsing boost's SSL asio code, async_write_some hangs
    primarykey
    data
    text
    <p>I have some multi-threaded code that uses Boost's SSL ASIO library. The code is multi-threaded, but there's a mutex associated with each SSL connection and calls to <code>async_*</code> functions are done holding the mutex.</p> <p>I sometimes see my code grind to a halt. There's a stuck thread. The thread is stuck in <code>bio_write</code>. The stack trace looks this:</p> <pre><code>#0 0x00000000010a974f in bio_write () #1 0x00000000010a3529 in BIO_write () #2 0x000000000105fe72 in ssl3_write_pending () #3 0x0000000001060b02 in ssl3_write_bytes () #4 0x0000000000cce43a in boost::asio::ssl::detail::engine::do_write (this=0x1e618a0, data=0x234c7b0, length=189) at /usr/include/boost/asio/ssl/detail/impl/engine.ipp:294 #5 0x0000000000cce109 in boost::asio::ssl::detail::engine::perform(this=0x1e618a0, op=(int (boost::asio::ssl::detail::engine::*)(boost::asio::ssl::detail::engine * const, void *, std::size_t)) 0xcce3fc&lt;boost::asio::ssl::detail::engine::do_write(void*, unsigned long)&gt;, data=0x234c7b0, length=189, ec=..., bytes_transferred=0x7fff8ad74d48) at /usr/include/boost/asio/ssl/detail/impl/engine.ipp:219 #6 0x0000000000ccdd23 in boost::asio::ssl::detail::engine::write (this=0x1e618a0, data=..., ec=..., bytes_transferred=@0x7fff8ad74d48: 0) at /usr/include/boost/asio/ssl/detail/impl/engine.ipp:137 #7 0x0000000000dac504 in boost::asio::ssl::detail::write_op&lt;boost::asio::mutable_buffers_1&gt;::operator() (this=0x7fff8ad74d20, eng=..., ec=..., bytes_transferred=@0x7fff8ad74d48: 0) at /usr/include/boost/asio/ssl/detail/write_op.hpp:51 #8 0x0000000000da9d8a in boost::asio::ssl::detail::io_op&lt;boost::asio::basic_stream_socket&lt;boost::asio::ip::tcp, boost::asio::stream_socket_service&lt;boost::asio::ip::tcp&gt; &gt;, boost::asio::ssl::detail::write_op&lt;boost::asio::mutable_buffers_1&gt;, boost::asio::detail::write_op&lt;boost::asio::ssl::stream&lt;boost::asio::basic_stream_socket&lt;boost::asio::ip::tcp, boost::asio::stream_socket_service&lt;boost::asio::ip::tcp&gt; &gt; &gt;, boost::asio::mutable_buffers_1, boost::asio::detail::transfer_all_t, boost::_bi::bind_t&lt;void, boost::_mfi::mf2&lt;void, Peer, boost::system::error_code const&amp;, unsigned long&gt;, boost::_bi::list3&lt;boost::_bi::value&lt;boost::shared_ptr&lt;Peer&gt; &gt;, boost::arg&lt;1&gt; (*)(), boost::arg&lt;2&gt; (*)()&gt; &gt; &gt; &gt;::operator() (this=0x7fff8ad74d10, ec=..., bytes_transferred=0, start=1) at /usr/include/boost/asio/ssl/detail/io.hpp:136 #9 0x0000000000da7f42 in boost::asio::ssl::detail::async_io&lt;boost::asio::basic_stream_socket&lt;boost::asio::ip::tcp, boost::asio::stream_socket_service&lt;boost::asio::ip::tcp&gt; &gt;, boost::asio::ssl::detail::write_op&lt;boost::asio::mutable_buffers_1&gt;, boost::asio::detail::write_op&lt;boost::asio::ssl::stream&lt;boost::asio::basic_stream_socket&lt;boost::asio::ip::tcp, boost::asio::stream_socket_service&lt;boost::asio::ip::tcp&gt; &gt; &gt;, boost::asio::mutable_buffers_1, boost::asio::detail::transfer_all_t, boost::_bi::bind_t&lt;void, boost::_mfi::mf2&lt;void, Peer, boost::system::error_code const&amp;, unsigned long&gt;, boost::_bi::list3&lt;boost::_bi::value&lt;boost::shared_ptr&lt;Peer&gt; &gt;, boost::arg&lt;1&gt; (*)(), boost::arg&lt;2&gt; (*)()&gt; &gt; &gt; &gt; (next_layer=..., core=..., op=..., handler=...) at /usr/include/boost/asio/ssl/detail/io.hpp:322 #10 0x0000000000da634d in boost::asio::ssl::stream&lt;boost::asio::basic_stream_socket&lt;boost::asio::ip::tcp, boost::asio::stream_socket_service&lt;boost::asio::ip::tcp&gt; &gt; &gt;::async_write_some&lt;boost::asio::mutable_buffers_1, boost::asio::detail::write_op&lt;boost::asio::ssl::stream&lt;boost::asio::basic_stream_socket&lt;boost::asio::ip::tcp, boost::asio::stream_socket_service&lt;boost::asio::ip::tcp&gt; &gt; &gt;, boost::asio::mutable_buffers_1, boost::asio::detail::transfer_all_t, boost::_bi::bind_t&lt;void, boost::_mfi::mf2&lt;void, Peer, boost::system::error_code const&amp;, unsigned long&gt;, boost::_bi::list3&lt;boost::_bi::value&lt;boost::shared_ptr&lt;Peer&gt; &gt;, boost::arg&lt;1&gt; (*)(), boost::arg&lt;2&gt; (*)()&gt; &gt; &gt; &gt; (this=0x1e61880, buffers=..., handler=...) at /usr/include/boost/asio/ssl/stream.hpp:502 #11 0x0000000000da3032 in boost::asio::detail::write_op&lt;boost::asio::ssl::stream&lt;boost::asio::basic_stream_socket&lt;boost::asio::ip::tcp, boost::asio::stream_socket_service&lt;boost::asio::ip::tcp&gt; &gt; &gt;, boost::asio::mutable_buffers_1, boost::asio::detail::transfer_all_t, boost::_bi::bind_t&lt;void, boost::_mfi::mf2&lt;void, Peer, boost::system::error_code const&amp;, unsigned long&gt;, boost::_bi::list3&lt;boost::_bi::value&lt;boost::shared_ptr&lt;Peer&gt; &gt;, boost::arg&lt;1&gt; (*)(), boost::arg&lt;2&gt; (*)()&gt; &gt; &gt;::operator() (this=0x7fff8ad74f00, ec=..., bytes_transferred=0, start=1) at /usr/include/boost/asio/impl/write.hpp:250 #12 0x0000000000d9ffbb in boost::asio::async_write&lt;boost::asio::ssl::stream&lt;boost::asio::basic_stream_socket&lt;boost::asio::ip::tcp, boost::asio::stream_socket_service&lt;boost::asio::ip::tcp&gt; &gt; &gt;, boost::asio::mutable_buffers_1, boost::_bi::bind_t&lt;void, boost::_mfi::mf2&lt;void, Peer, boost::system::error_code const&amp;, unsigned long&gt;, boost::_bi::list3&lt;boost::_bi::value&lt;boost::shared_ptr&lt;Peer&gt; &gt;, boost::arg&lt;1&gt; (*)(), boost::arg&lt;2&gt; (*)()&gt; &gt; &gt; (s=..., buffers=..., handler=...) at /usr/include/boost/asio/impl/write.hpp:585 </code></pre> <p>Any ideas?</p>
    singulars
    1. PO
      singulars
      1. PTAnswer
    1. This table or related slice is empty.
    1. PTQuestion
    1. This table or related slice is empty.
    1. USDavid Schwartz
    plurals
    1. PL
      singulars
      1. LTLinked
    2. PL
      singulars
      1. LTLinked
    1. PL
      singulars
      1. LTLinked
    1. This table or related slice is empty.
    1. PO
      singulars
      1. PTAnswer
    2. PO
      singulars
      1. PTAnswer
    1. VO
      singulars
      1. POUsing boost's SSL asio code, async_write_some hangs
      1. This table or related slice is empty.
      1. VTUpMod
    2. VO
      singulars
      1. POUsing boost's SSL asio code, async_write_some hangs
      1. This table or related slice is empty.
      1. VTUpMod
    1. COThe boost version might be relevant, can you add that to your question? I say this because the SSL implementation was rewritten in boost 1.47.
      singulars
      1. POUsing boost's SSL asio code, async_write_some hangs
      1. USSam Miller
    2. COIs it safe to assume this is the only [outstanding write](http://www.boost.org/doc/libs/release/doc/html/boost_asio/reference/async_write/overload1.html) operation for the stream? Doing otherwise may result in undefined behavior. As an example, it isn't sufficient to `lock mutex; async_write(...); unlock mutex;` as the operation is still in flight until the completion handler is invoked.
      singulars
      1. POUsing boost's SSL asio code, async_write_some hangs
      1. USSam Miller
    3. COBoost 1.50. I double checked that our one outstanding write logic is correct. We set a flag when we post a write and clear it when it completes. We do not post a write if the flag is set. (We do have `async_read` and `async_write` outstanding at the same time.) We might do an `async_shutdown` with a write pending. Is that safe?
      singulars
      1. POUsing boost's SSL asio code, async_write_some hangs
      1. USDavid Schwartz
 

Querying!

 
Guidance
A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.

SQuiL has stopped working due to an internal error.

If you are curious you may find further information in the browser console, which is accessible through the devtools (F12).

Reload