deadlock

问题 What could be the cause if a call to pthread_cond_signal deadlocks? From what I understand (man page), it is implemented internally with a mutex, but what could cause this internal mutex lock operation to deadlock? EDIT: I am debugging an application which seem to deadlock on some occasions. A few of the stacktraces look like this: Thread 1 (Thread 0xf6dff6c0 (LWP 32001)): #0 0xffffe410 in __kernel_vsyscall () #1 0x00af15de in __lll_mutex_lock_wait () from /lib/tls/libpthread.so.0 #2

问题 I found article(https://habr.com/company/odnoklassniki/blog/255067/) from the @apangin(https://stackoverflow.com/users/3448419/apangin) on my native langugage but I am not able to understand it. Explanation is very concise Let's consider that code: static class A { static final B b = new B(); } static class B { static final A a = new A(); } public static void main(String[] args) { new Thread(A::new).start(); new B(); } You could try to run that code. On my pc it leads to deadlockwith 75%

问题 I have two parts to my application which both does massive amount of insert and update respectively and because or poor managemenent, there's deadlock. I am using entity framework to do my insert and update. The following is my code for my TestSpool program. The purpose of this program is to insert x number of records with a given interval. using System; using System.Linq; using System.Threading; using System.Transactions; namespace TestSpool { class Program { static void Main(string[] args)

问题 I have to admit I'm just learning about properly handling deadlocks but based on suggestions I read, I thought this was the proper way to handle it. Basically I have many processes trying to 'reserve' a row in the database for an update. So I first read for an available row, then write to it. Is this not the right way? If so, how do I need to fix this SP? CREATE PROCEDURE [dbo].[reserveAccount] -- Add the parameters for the stored procedure here @machineId varchar(MAX) AS BEGIN SET

问题 I am experiencing a deadlock issue with HttpClient calls. I am guessing the deadlock is the result of my incomplete knowledge about async programming and I am doing something wrong. I have simplified the actual code into the example below, but I have maintained the same method call sequence and structure. I will be grateful for some insides on what could be causing the deadlock and suggestions on how to overcome this issue. I created an extension class for HttpClient, which has the following

问题 I am a newbie to Java EE. I wonder if there are some common deadlock cases in Java EE application layer, resulting from using Java synchronization primitive - synchronized keyword. If yes, could help give an example? 回答1: From the EJB 3.1 spec, Chapter 21.2.2. Programming Restrictions: An enterprise bean must not use thread synchronization primitives to synchronize execution of multiple instances, except if it is a Singleton session bean with bean-managed concurrency. And the reasoning is

问题 I'm new to C# and I'm very likely misunderstanding the the proper usage of await,async and Tasks :) I want to develop a class ( OWConnector ) that serves as API client for my app, for this purpose I develop a generic PostRequest method to perform POST request. Unfortunately the app looks like is going into a deadlock when I user the auth method (that uses the generic method PostRequest ). Can you help me to understand where is the problem ? I marked in the code where the debugger await

问题 i'm trying to realize fetch request, but it seems to be in deadlock. > Thread 1, Queue : com.apple.main-thread > #0 0x38329fa8 in __psynch_mutexwait () > #1 0x38390f0e in _pthread_mutex_lock () > #2 0x2d3aaad0 in -[_PFLock lock] () > #3 0x2d3bbba4 in -[NSPersistentStoreCoordinator executeRequest:withContext:error:] () > #4 0x2d3ba7e6 in -[NSManagedObjectContext executeFetchRequest:error:] () > #5 0x2d448bb6 in -[NSManagedObjectContext(_NestedContextSupport) _parentObjectsForFetchRequest

问题 I'm working on mysql5.6.34 with innoDB . There is a deadlock happened and I get following with show engine innodb status . I don't know how the deadlock happened, and why the TRANSACTION-2 holds and waiting for the same X lock, and then ROLLBACK it? logs: ------------------------ LATEST DETECTED DEADLOCK ------------------------ 2018-08-15 05:58:56 7fdff5872700 *** (1) TRANSACTION: TRANSACTION 81567872, ACTIVE 0 sec inserting mysql tables in use 1, locked 1 LOCK WAIT 4 lock struct(s), heap

问题 Please bear with me because I'm hopeless on vocabulary, and my own searches aren't going anywhere. I've learned here that if I update in the way I want to here (with the GROUP_CONCAT s also stored in user-defined vars), I'll lock the entire table. I'm fairly certain the best way to do this would be to UPDATE row by row in a CURSOR , starting with the highest PK id then descending because I'm sure I will have a lower chance of a deadlock, or conflict, or whatever it's called (told you I was