Boost C++ Libraries: Ticket #11499: windows - exception lock_error while intensive locking/unlocking of shared_mutex on many threads

version changed

Mon, 27 Jul 2015 21:58:36 GMT

version Boost 1.57.0 → Boost 1.58.0

version changed

Mon, 27 Jul 2015 22:50:30 GMT

version Boost 1.58.0 → Boost 1.59.0

component changed; owner set

Mon, 27 Jul 2015 22:53:47 GMT

owner set to Anthony Williams
component None → thread

Thu, 30 Jul 2015 07:25:25 GMT

Replying to andrew maclean <agm@…>:

#include "stdafx.h"
#include <boost/thread/shared_mutex.hpp>
#include <thread>
#include <mutex>
#include <shared_mutex>
#include <atomic>
#include <vector>
using MutexT = boost::shared_mutex;
using ReaderLockT = std::lock_guard<MutexT>;
using WriterLockT = std::shared_lock<MutexT>;
MutexT gMutex;
std::atomic<bool> running = true;
void threadfunc()
{
   while (running)
   {
      ReaderLockT lock(gMutex);  // exception - eventually... (ymmv)
      std::this_thread::yield();
   }
}
int main()
{
   using namespace std;
   vector<thread> threads;
   for (int i = 0; i < 256; ++i)
   {
      threads.emplace_back(thread(threadfunc));
   }
   string str;
   getline(std::cin, str);
   running = false;
   for (auto& thread : threads)
   {
      thread.join();
   }
   return 0;
}

owner, status changed

viboes — Wed, 05 Aug 2015 16:48:17 GMT

owner changed from Anthony Williams to viboes
status new → assigned

viboes — Wed, 05 Aug 2015 17:26:40 GMT

I'm unable to reproduce it on a MAC (I don't have a Windows machine available). Please, could you give more information?

attachment set

agm@… — Wed, 05 Aug 2015 22:35:37 GMT

attachment → shared_mutex_exception.png

viboes — Thu, 13 Aug 2015 06:49:02 GMT

Where your example is using timed_lock?

Thu, 13 Aug 2015 08:03:03 GMT

In shared_mutex.hpp @393 lock() member function

void lock() {

#if defined BOOST_THREAD_USES_DATETIME

BOOST_VERIFY(timed_lock(::boost::detail::get_system_time_sentinel()));

#else

BOOST_VERIFY(try_lock_until(chrono::steady_clock::now()));

#endif

}

viboes — Thu, 03 Sep 2015 07:06:43 GMT

Please, could you try using a version >= 0

#define BOOST_THREAD_VERSION 4
#include <boost/thread/shared_mutex.hpp>
....

If you can not, could you try replacing

 #if defined BOOST_THREAD_USES_DATETIME
    BOOST_VERIFY(timed_lock(::boost::detail::get_system_time_sentinel()));
#else
    BOOST_VERIFY(try_lock_until(chrono::steady_clock::now()));
#endif

    BOOST_VERIFY(try_lock_until(chrono::steady_clock::now()));

The same for lock_shared.

Thanks for your help, Vicente

viboes — Tue, 08 Sep 2015 17:31:33 GMT

https://github.com/boostorg/thread/commit/b30cde32d4d90f601acc136bd02a4cdcbf3ea602

viboes — Sun, 27 Sep 2015 13:19:58 GMT

It seems this change doesn't works at all. I've rolled back the change.

summary changed

viboes — Sun, 06 Dec 2015 09:20:08 GMT

summary exception lock_error while intensive locking/unlocking of shared_mutex on many threads → windows - exception lock_error while intensive locking/unlocking of shared_mutex on many threads

viboes — Mon, 15 Aug 2016 17:59:25 GMT

You can define BOOST_THREAD_PROVIDES_GENERIC_SHARED_MUTEX_ON_WIN to get the generic implementation. It is slower but IMHO it has less bugs.

See #12386