interlocked

问题 The Interlocked.CompareExchange() method (docs) does roughly speaking this: "I have a variable, and I think I know what value it currently has. If I'm right, then please change the value to that". The point being that this method can be used to safely update a variable in a multi-threaded context. If the value has changed since the caller thought it knew what the value was, then some other thread has made that change, so this thread needs to retry (or whatever other behaviour is appropriate)

问题 This question already has answers here : C# Closures, why is the loopvariable captured by reference? (6 answers) Why does resharper suggest “wrap variable in array” for access to modified closure warnings? (2 answers) ReSharper Warning - Access to Modified Closure (1 answer) Closed last year . I have code like this (simplified): long counter = 0L; var t = Task.Run(async () => { Interlocked.Increment(ref counter); // Resharper: "Access to modified closure" await Task.Delay(500); // some work }

问题 While I was reading about ReaderWriterLockSlim lock mechanism , There was this guy who suggested that Interlock Functions can be used for a finer locking Also, I found here another answer from Marc : ...Writes make their change to a cloned copy, then use Interlocked.CompareExchange to swap the reference (re-applying their change if another thread mutated the reference in the interim). Well , Currently all I know about Interlocked object , is that it is used (in a multithreaded environment) to

问题 While I was reading about ReaderWriterLockSlim lock mechanism , There was this guy who suggested that Interlock Functions can be used for a finer locking Also, I found here another answer from Marc : ...Writes make their change to a cloned copy, then use Interlocked.CompareExchange to swap the reference (re-applying their change if another thread mutated the reference in the interim). Well , Currently all I know about Interlocked object , is that it is used (in a multithreaded environment) to

问题 Interlocked.Increment seems like among the most standard/simple of operations one would need to perform in multithreaded code. I assume that the functionality of the method is some sort pattern that anyone with threading experience would be able to replicate. So basically what I am wondering is if someone could provide an exact duplicate (with explanation of how it works) of what the Interlocked.Increment method is actually doing internally? (I have looked for the source of the actual method

问题 I have a bit of my game which looks like this: public static float Time; float someValue = 123; Interlocked.Exchange(ref Time, someValue); I want to change Time to be a Uint32; however, when I try to use UInt32 instead of float for the values, it protests that the type must be a reference type. Float is not a reference type, so I know it's technically possible to do this with non-reference types. Is there any practical way to make this work with UInt32 ? 回答1: Although ugly, it is actually

问题 When performing a MemberwiseClone of an array of value types: var arr = new double[100]; If these doubles are being modified using an Interlocked write on other threads, will the MemberwiseCloned copy be at any risk of having torn doubles in it? I'm not concerned about having slightly stale values, just tearing and the interaction between interlocked and memberwiseclone (which I guess translates to a memory blit type operation?) 回答1: Yes. On 32bit operating systems this is even guaranteed to

问题 I was testing how Interlocked.Increment and lock behave on my computer's architecture because I read the following lines in this article. As rewritten with Interlocked.Increment, the method should execute faster, at least on some architectures. Using the following code I get convinced that it's worth to review locks in my projects. var watch = new Stopwatch(); var locker = new object(); int counter = 0; watch.Start(); for (int i = 0; i < 100000000; i++) { lock (locker) { counter++; } } watch

问题 Suppose I have a variable "counter", and there are several threads accessing and setting the value of "counter" by using Interlocked, i.e.: int value = Interlocked.Increment(ref counter); and int value = Interlocked.Decrement(ref counter); Can I assume that, the change made by Interlocked will be visible in all threads? If not, what should I do to make all threads synchronize the variable? EDIT: someone suggested me to use volatile. But when I set the "counter" as volatile, there is compiler

问题 In one of our old services I found such piece of code (comments are original): long[] tasksCounter = {0}; //boxing for long counters long[] errorsCounter = {0}; //boxing for long counters Further in the code these "arrays" are used with Interlocked class: Interlocked.Increment(ref errorsCounter[0]) , Interlocked.Read(ref errorsCounter[0]) etc). I wonder why did not the author use basicaly long tasksCounter, errorsCounter ? Probably this approach has benefits I don't know about? It's probably