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Questions tagged [spinwait]

A spin-wait loop is a technique used in multithreaded applications whereby one thread waits for other threads for protecting a critical section, for barriers, or for other synchronizations.

A spin-wait loop is a technique used in multithreaded applications whereby one thread waits for other threads for protecting a critical section, for barriers, or for other synchronizations.

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Why there is a Thread.Sleep(1) in .NET internal Hashtable?

Recently I was reading implementation of .NET Hashtable and encountered piece of code that I don't understand. Part of the code is: int num3 = 0; int num4; do { num4 = this.version; bucket = bucketArray[index]; if (++num3 % 8 == 0) …
Dariusz Woźniak
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Are there any examples in the .Net framework that use spinlock or spinwait?

I had a look at the concurrent collections but they appear to use normal locking underneath the hood. Are there any good examples in the .Net framework that use this locking construct? I initially looked at ConcurrentDictionary. I saw it was using…
uriDium
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Should interlocked implementations based on CompareExchange use SpinWait?

Below is an implementation of an interlocked method based on Interlocked.CompareExchange. Is it advisable for this code to use a SpinWait spin before reiterating? public static bool AddIfLessThan(ref int location, int value, int comparison) { …
Timo
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Calling thread.sleep() while waiting for a new thread to spawn

I suppose this question can be boiled down to "SpinWait vs. Block?", but I figured there may be a more interesting answer as to why nearly every C# threading tutorial suggests the following call: Thread newThread = new Thread(new…
wger
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SpinWait in lockless update

While reading Albahari's Threading in C#, I've noticed that the "lock free update" pattern uses a SpinWait at the end of the cycle: static void LockFreeUpdate (ref T field, Func updateFunction) where T : class { var spinWait = new…
Lou
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Why do you need SpinWait in LockFreeUpdate sample from Albahari's "Threading in C#"

I am working on small Ref abstraction with lock-free optimistic Update method (supposed to work with immutable T data structures, immutable trees in particular). It is based on Albahari's "Threading in C#" LockFreeUpdate method in SpinWait usage…
dadhi
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How is NET 4.0 SpinWait method different to pre-4.0 SpinWait()?

MSDN "Thread-Safe Collections .NET Framework 4" states: "Some of the concurrent collection types use lightweight synchronization mechanisms such as SpinLock, SpinWait, SemaphoreSlim, and CountdownEvent, which are new in the .NET Framework…
Fulproof
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SpinWait.SpinUntil taking MUCH longer than timeout to exit while waiting for Selnium element to exist

I have a relatively simple method to wait until an element exists and is displayed. The method handles the situation where more than a single element is returned for the given By (usually we only expect one of them to be displayed but in any case…
Ory Zaidenvorm
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Spin wait C++11

I have the following struct struct info { unsigned long a; unsigned long b; }; atomic data; used by a writer thread and a reader thread. The reader has to respond to the new values as fast as possible. To do that I’ve implemented the…
toco
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What is the equivalent of Windows .NET (C++) SpinWait on Linux and Mac OS X?

Windows .NET (C++) provides SpinWait for Hyper-threading friendly busy waiting with YIELD/PAUSE instructions. What is the equivalent function on Linux and Mac OS X? If a system call isn't available, how can an equivalent be implemented in user…
Coder
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Power preserving SpinWait

I have a polling loop in C# that needs to poll every 100 microseconds on average < EDIT> (given of course that there is no excessive preemptive thread context switch carried out by Windows due to core shortage) < /EDIT>. As there is no time for a…
Jack Wester
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Why have AMD-CPUs such a silly PAUSE-timing

I've developed a monitor-object like that of Java for C++ with some improvements. The major improvement is that there's not only a spin-loop for locking and unlocking but also for waiting on an event. In this case you don't have to lock the mutex…
Bonita Montero
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Random Numbers in For Loops

Hi I have searched all over the internet for this answer and please let me explain before i get into the actual problem. it may seem simple to but the only choices that really helped me was Thread.Sleep and Thread.SpinWait but it basically stops my…
Green Bray Games LLC
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nutch crawling gets stuck in spinwaiting or active. how to reduce fetch cycle?

I am using nutch 2.1 and crawling a site. The problem is that the crawler keeps showing fetching url spinwaiting/active and since the fetching takes so much time the connection to mysql gets timedout. How can i reduce the number of fetches at a time…
peter
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Thread.SpinWait seems to be affected by the main thread

I’m using Thread.SpinWait on a special thread to create a near-exact 2ms delay with minimal chance of a context switch, needed for precise hardware communication timing. But using a profiler, I’ve noticed that if the main thread does something that…
Dreamwriter
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