Support Requests item #1280829, was opened at 2005-09-02 10:06 Message generated for change (Tracker Item Submitted) made by Item Submitter You can respond by visiting: https://sourceforge.net/tracker/?func=detail&atid=207586&aid=1280829&group_id=7586 Please note that this message will contain a full copy of the comment thread, including the initial issue submission, for this request, not just the latest update. Category: None Group: None Status: Open Resolution: None Priority: 5 Submitted By: Nobody/Anonymous (nobody) Assigned to: Nobody/Anonymous (nobody) Summary: Multithreaded process pausing but not deadlocking or crashin Initial Comment: Hi, I am writing a largely multithreaded linux program (20-60 threads) on version Fedora Core 2. I am using glib c version 2.3.3-27. In addition, I am using the boost libraries (version 1.32.0) for my threading and locking. Specifically, I am using mutexes, recursive_mutexes, scoped locking, and conditions. My problem is that the process will suddenly cease activity for random lengths of time (1 sec to minutes). However, it never crashes or produces incorrect results. Also, I do not think that it is deadlocking because it always resumes its activity. I have done some profiling of the locks, and it shows very strange behavior. For instance, threads will block for long lengths of time (the length of the inactivity) while no thread is holding the corresponding mutex more than fractions of a second. When I explored this further, it appears that thread A is blocking on a mutex while thread B holds it. I am using boost::recursive_mutex::scoped_lock objects for the locking. The weird thing is that thread B pauses at the very end of the lock's scope (again for a the length of inactivity), as though the attempt to unlock the mutex is not waking thread A and descheduling thread B for a long time. I created a test program that spawns 30 threads that just do a bunch of locking of these boost scoped locks and yielding. This program, too, shows the same downtime activity (again without crashing or deadlocking), though less frequently (I suspect because the locking pattern is probably different than in my program). It also always resumes its activity eventually. I have attached the test program code. I'm not sure whether this is a problem with the boost libraries or a linux problem, or my own problem. I was wondering if anyone has experienced similar behavior and might be able to offer some insight or guidance. Thanks! Matt ---------------------------------------------------------------------- You can respond by visiting: https://sourceforge.net/tracker/?func=detail&atid=207586&aid=1280829&group_id=7586 ------------------------------------------------------- SF.Net email is Sponsored by the Better Software Conference & EXPO September 19-22, 2005 * San Francisco, CA * Development Lifecycle Practices Agile & Plan-Driven Development * Managing Projects & Teams * Testing & QA Security * Process Improvement & Measurement * http://www.sqe.com/bsce5sf _______________________________________________ Boost-bugs mailing list Boost-bugs@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/boost-bugs