Here is some scaled down code of generally what I'm doing: ----------------------------------------------------------------------------------------------- boost::thread_specific_ptr <ifstream> infile; boost::thread_specific_ptr< std::vector<std::string> > file_buffer; boost::thread_specific_ptr<std::string> TempLine; //more ptrs here void ReadFile(wxString FileName) { infile.reset(new ifstream); file_buffer.reset ( new std::vector<std::string> ); TempLine.reset ( new std::string ); //init other ptrs here //open file, etc here (@infile) //read contents into vector line by line while ( ! infile.get()->eof() ) { getline(*infile,*TempLine); file_buffer.get()->push_back(*TempLine); } //other operations on file_buffer below ........... } void CallFunc() { boost::filesystem::path p(TEMP_PATH); //refers to class member boost::filesystem::directory_iterator itr(p); boost::filesystem::directory_entry & entry = *itr; boost::filesystem::directory_iterator end_itr; std::vector< boost::thread* > t; int total_files = std::count_if( directory_iterator(p), directory_iterator(), bind( static_cast<bool(*)(const path&)>(is_regular_file), bind( &directory_entry::path, _1 ) ) ); for (; itr!=end_itr; ++itr) { //read files, create threads t.push_back( new boost::thread(&ReadFile, this, entry.path().filename().string() ) ) ; t->join(); //app freezes here, if i detach() instead of join it's fine //some other stuff } //delete thread pointers, etc ( join() before delete ) } ------------------------------------------------------------------------------------------------ Hope that helps On Sun, Nov 24, 2013 at 12:07 PM, Igor R <boost.lists@gmail.com> wrote:
I am using multiple threads for I/O operations. The issue I am having is joining these threads on the main thread. It appears that calling join() on a thread with TLS pointers, it results in a hang.
Could you provide a small self-contained repro, or at least show some code?
Another thing to note is that when calling detach() on the thread, all of the threads execute properly and I get expected output. However, I need to call join() every x amount of threads due to OS limitations of how many threads can actually be created. I need to read about 5000 files so obviously I can't create 5000 threads as Windows maxes out at 700 I believe. I am reading files off of a RAID setup so I believe this is a situation
<...> that
can benefit from multiple threads reading files.
Creating threads for i/o is not an efficient/scalable approach. Consider using Boost.Asio instead (in particular, see the following example http://www.boost.org/doc/libs/1_55_0/doc/html/boost_asio/example/cpp03/windo... ) _______________________________________________ Boost-users mailing list Boost-users@lists.boost.org http://lists.boost.org/mailman/listinfo.cgi/boost-users
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