Questions tagged [concurrency]
In computer science, concurrency is a property of systems in which multiple computations can be performed in overlapping time periods. The computations may be executing on multiple cores in the same chip, preemptively time-shared threads on the same processor, or executed on physically separated processors.
concurrency
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What is the difference between concurrency and parallelism?
What is the difference between concurrency and parallelism?
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How do I use threading in Python?
I would like a clear example showing tasks being divided across multiple threads.
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answers
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What is a race condition?
When writing multithreaded applications, one of the most common problems experienced is race conditions.
My questions to the community are:
What is the race condition?
How do you detect them?
How do ...
- 30.6k
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Collection was modified; enumeration operation may not execute
I can't get to the bottom of this error, because when the debugger is attached, it does not seem to occur.
Collection was modified; enumeration operation may not execute
Below is the code.
This is a ...
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When and how should I use a ThreadLocal variable?
When should I use a ThreadLocal variable?
How is it used?
Sasha
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What is a mutex?
A mutex is a programming concept that is frequently used to solve multi-threading problems. My question to the community:
What is a mutex and how do you use it?
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Why there is no ConcurrentHashSet against ConcurrentHashMap
HashSet is based on HashMap.
If we look at HashSet<E> implementation, everything is been managed under HashMap<E,Object>.
<E> is used as a key of HashMap.
And we know that HashMap ...
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Is JavaScript guaranteed to be single-threaded?
JavaScript is known to be single-threaded in all modern browser implementations, but is that specified in any standard or is it just by tradition? Is it totally safe to assume that JavaScript is ...
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What is the difference between lock, mutex and semaphore?
I've heard these words related to concurrent programming, but what's the difference between lock, mutex and semaphore?
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What's the difference between ConcurrentHashMap and Collections.synchronizedMap(Map)?
I have a Map which is to be modified by several threads concurrently.
There seem to be three different synchronized Map implementations in the Java API:
Hashtable
Collections.synchronizedMap(Map)
...
- 11.6k
495
votes
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NSOperation vs Grand Central Dispatch
I'm learning about concurrent programming for iOS. So far I've read about NSOperation/NSOperationQueue and GCD. What are the reasons for using NSOperationQueue over GCD and vice versa?
Sounds like ...
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Custom thread pool in Java 8 parallel stream
Is it possible to specify a custom thread pool for Java 8 parallel stream? I can not find it anywhere.
Imagine that I have a server application and I would like to use parallel streams. But the ...
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What is the meaning of the term "thread-safe"?
Does it mean that two threads can't change the underlying data simultaneously? Or does it mean that the given code segment will run with predictable results when multiple threads are executing that ...
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How to wait for all threads to finish, using ExecutorService?
I need to execute some amount of tasks 4 at a time, something like this:
ExecutorService taskExecutor = Executors.newFixedThreadPool(4);
while(...) {
taskExecutor.execute(new MyTask());
}
//......
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What is a semaphore?
A semaphore is a programming concept that is frequently used to solve multi-threading problems. My question to the community:
What is a semaphore and how do you use it?
- 30.6k