multithreading - What is a deadlock? - Stack Overflow
2008年8月29日 · 2. A deadlock occurs when there is a circular chain of threads or processes which each hold a locked resource and are trying to lock a resource held by the next element in the chain. For example, two threads that hold respectively lock A and lock B, and are both trying to acquire the other lock.
multithreading - Simple Deadlock Examples - Stack Overflow
2009年9月6日 · public String getName() {. return name; public void setName(String name) {. this.name = name; In the above example 2 threads are executing the synchronized methods of two different objects. Synchronized methodA is called by object threadDeadLockA and synchronized methodB is called by object threadDeadLockB.
What are common reasons for deadlocks? - Stack Overflow
2009年6月29日 · Stephen Toub in the MSDN article Deadlock monitor states the following four conditions necessary for deadlocks to occur: A limited number of a particular resource. In the case of a monitor in C# (what you use when you employ the lock keyword), this limited number is one, since a monitor is a mutual-exclusion lock (meaning only one thread can ...
Deadlocks in Oracle - Stack Overflow
2015年2月11日 · Oracle detects a deadlock automatically, throws ORA-00060: deadlock detected while waiting for resource, and rolls back one of the transactions involved in the deadlock which Oracle decided as the victim. The previous successful transactions are not rolled back.
What is a deadlock in a database? - Stack Overflow
2010年5月5日 · What is a deadlock. A deadlock happens when two concurrent transactions cannot make progress because each one waits for the other to release a lock, as illustrated in the following diagram. Because both transactions are in the lock acquisition phase, neither one releases a lock prior to acquiring the next one. Recovering from a deadlock situation
Difference between racearound condition and deadlock
2013年10月15日 · 11. Unlock(y) 12. Unlock(y) You can see that a deadlock occurs at time 7 because T2 tries to acquire a lock on x but T1 already holds the lock on x but it is waiting on a lock for y, which T2 holds. This bad. You can turn this diagram into a dependency graph and you will see that there is a cycle.
An async/await example that causes a deadlock - Stack Overflow
In these single-threaded synchronization contexts, it’s easy to deadlock yourself. If you spawn off a task from a single-threaded context, then wait for that task in the context, your waiting code may be blocking the background task. public ActionResult ActionAsync() {. // DEADLOCK: this blocks on the async task. var data = GetDataAsync().Result;
What's the difference between deadlock and livelock?
2011年5月27日 · DEADLOCK Deadlock is a condition in which a task waits indefinitely for conditions that can never be satisfied - task claims exclusive control over shared resources - task holds resources while waiting for other resources to be released - tasks cannot be forced to relinguish resources - a circular waiting condition exists
sql server - how to solve deadlock problem? - Stack Overflow
2009年10月1日 · 6. A common issue with high isolation is lock escalation deadlocks due the the following scenario; i.e. (where X is any resource, such as a row) SPID a reads X - gets a read lock. SPID b reads X - gets a read lock. SPID a attempts to update X - …
c# - await vs Task.Wait - Deadlock? - Stack Overflow
2012年10月30日 · 388. Wait and await - while similar conceptually - are actually completely different. Wait will synchronously block until the task completes. So the current thread is literally blocked waiting for the task to complete. As a general rule, you should use " async all the way down"; that is, don't block on async code.