deadlock

问题 I just want someone to help me in this, because I want a function that can check deadlock for the below code. So, by checking the deadlock we will get the execution order of the process. If its in safe state with no deadlock and if there is a deadlock, just print out false. But I could not do it in Prolog, so can someone help me out to modify the below code to make it print false if its having a deadlock? processes([1,2,3,4]). request(1,r1). request(3,r2). allocated(1,r2). allocated(2,r1).

问题 What are the ways to detect deadlocks in a live multi-threaded application? If we found there is a deadlock, are there any ways to resolve it, without taking down/restarting the application? 回答1: There are two popular ways to detect deadlocks. One is to have threads set checkpoints. For example, if you have a thread that has a work loop, you set a timer at the beginning of doing work that's set for longer than you think the work could possibly take. If the timer fires, you assume the thread

问题 What are the ways to detect deadlocks in a live multi-threaded application? If we found there is a deadlock, are there any ways to resolve it, without taking down/restarting the application? 回答1: There are two popular ways to detect deadlocks. One is to have threads set checkpoints. For example, if you have a thread that has a work loop, you set a timer at the beginning of doing work that's set for longer than you think the work could possibly take. If the timer fires, you assume the thread

问题 What are the ways to detect deadlocks in a live multi-threaded application? If we found there is a deadlock, are there any ways to resolve it, without taking down/restarting the application? 回答1: There are two popular ways to detect deadlocks. One is to have threads set checkpoints. For example, if you have a thread that has a work loop, you set a timer at the beginning of doing work that's set for longer than you think the work could possibly take. If the timer fires, you assume the thread

问题 Quote from java concurrency in practice: Using timed lock acquisition to acquire multiple locks can be effective against deadlock even when timed locking is not used consistently throughout the program. If a lock acquisition times out, you can release the locks, back off and wait for a while, and try again, possibly clearing the deadlock condition and allowing the program to recover. ( This technique works only when the two locks are acquired together; if multiple locks are acquired due to

问题 While subscribing to a Reactive Extensions Flowable stream, I noticed the stream halts/hangs (no more future items are emitted, and no error is returned) after 128 items have been returned. val download: Flowable<DownloadedRecord> = sensor.downloadRecords() download .doOnComplete { Log.i( "TEST", "Finished!" ) } .subscribe( { record -> Log.i( "TEST", "Got record: ${record.record.id}; left: ${record.recordsLeft}" ) }, { error -> Log.i( "TEST", "Error while downloading records: $error" ) } )

问题 ffmpeg feels like its taking a long time. I then look at my output file and i see it stops between 6 and 8mbs. A fully encoded file is about 14mb. Why does ffmpeg stop? My code locks up on StandardOutput.ReadToEnd();. I had to kill the process (after seeing it not move for more then 10 seconds when i see it update every second previously) then i get the results of stdout and err. stdout is "" stderr is below. The output msg shows the filesize ended. I also see a drop in my CPU usage when it

问题 I am having a problem with pthreads where i think i am getting a deadlock. I have created a blocking queue which I thought was working, but after doing some more testing I have found that if i try and cancel multiple threads that are blocking on the blocking_queue, i seem to get a deadlock. The blocking queue is very simple and looks like this: template <class T> class Blocking_Queue { public: Blocking_Queue() { pthread_mutex_init(&_lock, NULL); pthread_cond_init(&_cond, NULL); } ~Blocking

问题 The Deadlock occurs in my application when initialization of local static variable happens in the function called from DLLMain Entry point with param DLL_THREAD_DETACH. Below is Windbg analysis This is usually caused by another thread holding the loader lock. Following are the Locks Held. CritSec ntdll!LdrpLoaderLock+0 at 7c97e178 LockCount 3 RecursionCount 1 OwningThread 17e8 EntryCount d ContentionCount d *** Locked CritSec MSVCR80!__app_type+94 at 781c3bc8 LockCount 1 RecursionCount 1

问题 I have a C application that uses pthreads. There is a lock contention between two threads(say A and B) where A gets the lock first while B is waiting for the lock, Once A is done and releases the lock, B still doesn't get it and after a while A gets the lock again(A does acquire and release in a loop). If I attach my process to gdb and pause thread A after it has given up the lock and manually continue on thread B, it then gets it and does what is needed. This does not look like a dead lock