[Boost-bugs] [Boost C++ Libraries] #4679: Memory Leak using Boost Threads with Indirect Usage of ADO .NET (CLR)

Subject: [Boost-bugs] [Boost C++ Libraries] #4679: Memory Leak using Boost Threads with Indirect Usage of ADO .NET (CLR)
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2010-09-23 00:53:22

#4679: Memory Leak using Boost Threads with Indirect Usage of ADO .NET (CLR)
----------------------------------+-----------------------------------------
 Reporter:  twc2102@…             |       Owner:  anthonyw
     Type:  Bugs                  |      Status:  new     
Milestone:  To Be Determined      |   Component:  threads 
  Version:  Boost 1.44.0          |    Severity:  Problem 
 Keywords:                        |  
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 I've noticed a significant memory leak when I use Boost Threads to
 repeatedly call a managed C++ function with an unmanaged interface.  The
 managed function executes a stored procedure using ADO .NET's
 ExecuteNonQuery.

 I created an executable that only loads data into SQL Server by repeatedly
 executing a stored procedure based on information in fixed files.  I make
 sure that all variables go out of scope before my executable ends with two
 lines, allowing me to see unreleased memory
 to that point

 char str [256];
 scanf_s("%s", &str, _countof(str));

 Without using any thread library, my exe would utilize 31MB of memory at
 scanf_s.  Using Boost threads with a pointer to a single thread that is
 created, joined, and deleted once for 32 files, I have 72MB of unreleased
 memory.  Using threadpool at http://threadpool.sourceforge.net/index.html

 with a pool of a single thread, I utilize 49MB of memory.

 If I increase the number of small files to 1,000 and increase the number
 of threads to 16, then the memory usage without a thread library is
 unchanged and the unreleased memory with a thread library can exceed 1GB.
 If I scale the size large enough, I run out of memory.

 Template Example with 72MB of unrelease memory
 {
      boost::thread *tp=0
      for (long i=0; i<32; i++) {
          tp=new boost::thread(Func)
          tp->Join();
          delete tp;
          tp=0;
      }
 }

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Ticket URL: <https://svn.boost.org/trac/boost/ticket/4679>
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