Questions tagged [thread-safety]

A piece of code is thread-safe if it only manipulates data structures in a way that allows consistent execution of this code by multiple threads.

5
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1answer
120 views

Async concurrency prevention class

Because I'm quite naive regarding C#'s Task Asynchronous Programming and concurrency in general, and because it's so difficult to test, I'm concerned about the safety of this code. It's likely that ...
2
votes
1answer
39 views

Thread-safe stack in Java with fixed capacity

Implement a multi-threaded stack, with freedom to use existing implementations of stack. On top of being thread-safe, it must block (not busy-wait) a pushing thread when stack is full and a ...
5
votes
1answer
52 views

Rate limiting variable-duration operations over a time interval

I want a rate-limiter that permits, at most, N operations over T seconds. I found a sample implementation here but it makes an assumption that operations complete in a predictable, consistent amount ...
3
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1answer
118 views

Determine concurrent access to a function

Someone asked here how to determine a function is being called from multiple threads. My take on this is that they are asking about concurrent access not sequential access. The accepted answer ...
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vote
0answers
35 views

Near immutable, thread safe Builder

I'm writing a torrent streaming client. The plan is to wrap WebTorrent-cli and provide a Java interface to observe download state, cancel or pause downloads etc. Anyways, I came up with the following ...
4
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0answers
221 views

Wait free triple buffer primitive

I'm trying to write a triple buffer that's wait free for a update + render loop after being bitten by lock starvation one too many times (on a different project, using a library). For reference, a ...
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vote
0answers
43 views

C# asynchronous notification vector v2

As a result of my previous post, I have implemented / refactored my code and have started making successful use of my class. However I have come across a couple of new questions: The observer must ...
2
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0answers
34 views

Comparing Java Semaphore versus ReentrantReadWriteLock

In this post, I attempted to compare the performance of two concurrency constructs: java.util.concurrent.Semaphore, ...
6
votes
1answer
84 views

C# asynchronous notification vector

The purpose of this class is to efficiently notify another thread when data is available with minimal blocking to access/pass the data. The data reader/producer thread processes data in bulk which ...
1
vote
1answer
57 views

Multithreading to allow multiple clients on to a server and client requests handling

I have to create a client-server JavaFX application using MVC which does many operations consisting mainly in messages exchange. I'd like to know if this way to handle client acceptance and client ...
1
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1answer
163 views

Java concurrency exercise, implementing transfer of amount from one account to another

This is in continuation with my synchronized implementation of a bank account in Java. I am trying to implement bank accounts repository and method to transfer money from one account to another. My ...
7
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2answers
873 views

Synchronized implementation of a bank account in Java

I am trying to implement a bank account with Java in a thread safe way. My code looks like: ...
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0answers
33 views

threaded event loop “interrupt” unit test without deadlocks

I have an event_loop implementation (basically an event/command queue and an exec function). I have added ...
5
votes
1answer
349 views

Implementation of thread-safe vector

I have implemented a thread safe vector, based on std::thread and std::vector. I am new to many of the patterns used in threading and was wondering if there's a more efficient way the locking can be ...
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0answers
71 views

An attempt of replacing CRITICAL_SECTION with std::mutex and std::lock_guard

I have an older class that I am working on and I'm updating it to remove "Windows" specific code. It had some "Thread Protection Code" that used CRITICAL_SECTION. I'...
1
vote
2answers
78 views

Thread-safe singleton cache (Python)

In a service I'm developing I'm using three cloud services (five if you count additional two streaming services I have to create that are used by those cloud services in turn) and to orchestrate bits ...
0
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0answers
40 views

Spring Component Thread Safe

Recently I refactored an application to start using spring, and after some research, I found out that @Component is not thread safe. The class is this: (It's a converter from xlsx to json string) <...
1
vote
1answer
30 views

Spring TaskScheduling with HashMap

I am currently developing a Task Scheduler to run different methods at a certain time. In general it is a Spring-boot application an task execution/scheduling is just a very tiny piece of the whole ...
2
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0answers
44 views

Thread-safe sensor interface with observer and strategy patterns

I have a thread-safe API for an observable Sensor. The concrete type of the Sensor is chosen in the ...
2
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0answers
106 views

thread safe queue with interrupt function

I try to implement a thread safe queue with the interrupt function (interrupt all threads who are blocking to take data from queue). ...
2
votes
1answer
77 views

Simple multithreading C project

I'm fairly new to C, and this is my first time using pthread. I am pretty sure I implemented it correctly, however I'd like to verify it is indeed executing the ...
2
votes
0answers
69 views

Repeating a task that may fail (in parallel)

Almost like this question here, I'm playing with some methods that may fail, but in my case, the method failing is not a exceptional case; it just means I need to try running it again. The method I'm ...
3
votes
0answers
61 views

“Lock-free” one-shot event manager

Giving a review to Oachkatzl and recently about some other synchronization problems (Lazy with invalidate and some node-locking list), I wanted to test my skills and redesign it in most light-weight ...
4
votes
3answers
109 views

Really easy synchronised access to an IEnumerable without boilerplate code

Often when reading data from a sequence (IEnumerable<T>) in multi-threaded code, a consistent snapshot needs to be taken inside a ...
5
votes
1answer
199 views

Linked list node-level locking

I am new to C++ threading library. I would love to get some comments on how to improve this code (if there are possible bugs, I would appreciate that feedback too). In particular, I want to refactor ...
1
vote
0answers
44 views

Multithreaded FRC Robot Framework (Kinda Big)

I'm working on some code for an FRC Robot. I wanted to see if there's any obvious improvements that can be made here, that stands out, or stuff I should avoid doing. This is a test bed for the base ...
7
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1answer
154 views

Threadsafe oneshot-event which fires on subscription if the event was fired in the past

Assumptions Basically, a Connection class has a "Disconnect" event. Subscribing to this event isn't thread-safe, because the disconnection may fire from another thread right before I subscribe. So ...
0
votes
1answer
1k views

Print odd and even numbers using two threads in Java

I was asked below question in an interview where I need to print out even and odd numbers using two threads so I came up with below code one without synchronization and other with synchronization. <...
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0answers
139 views

Thread-safe Java class for managing XML files <> domain models

This Java class (aka application component) role is to handle a series of XML files stored in the file system. It must convert those XML files to the corresponding application domain model, and it ...
1
vote
0answers
31 views

Drawing sprites and adding new ones

I have some code that draws sprites and and allows new ones to be added. To do this, I use 2 lists: 1 for the sprites that need to be drawn, and one for the new sprites that need to be added to the ...
3
votes
3answers
282 views

C++ upgradable RW lock implementation

I am using VS 2017 with C++ 17 standard set on Windows OS. What I'm missing in couple of heavily threaded projects is synchronizing mechanism that can be atomically upgraded from shared to exclusive ...
7
votes
4answers
710 views

Caching Color-Bitmaps as MemoryStreams

I am in the need to cache Bitmap's in a memory-optimized way because the API I am building will need to process many colored ...
1
vote
1answer
988 views

Static wrapper class for log4net Logging - thread safety

I'm using log4net in my application and have a static Log class which creates an instance of ...
2
votes
1answer
192 views

Run two computations in parallel, and return the results together

I am reading the "Learning Concurrent Programming in Scala" and there are exercises in the end of each chapter. One of exercises is Implement a parallel method which takes two computation blocks a ...
1
vote
1answer
221 views

Thread safe queue with buffer

I must implement thread-safe queue with buffer. According to the advice from the previous post: Thread-safe queue mechanism I resigned from Concurent Collections and used lock. Is it thread safe now? ...
-1
votes
1answer
364 views

Thread-safe queue mechanism

Is it my queue mechanism thread safe? I just wonder if I need concurrent collections. Need I lock Enqueue method? Console displays queue count in incorrect order, Does it affect on maxQueueCount at ...
2
votes
1answer
94 views

Synchronized template wrapper class

Issue: Code base has lots of data structures which are accessed between threads with >= 1 writer. Application logic becomes obfuscated due to lots of mutex locks. Solution: Create a template ...
9
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1answer
672 views

A thread-safe priority queue keeping its elements unique

This class is intended to be used in situations where queue.Queue does not suffice, because the following two properties are needed. Every item in the queue can ...
11
votes
1answer
138 views

C++ thread-safe averaging

Although having very little C++ experience, I was tasked to implement several statistics objects that are safe to be asynchronous accessed by different threads, that collect data in relatively small ...
3
votes
1answer
968 views

Simple rwlock implementation in c++11

For answering this question of stackoverflow I have written the code https://stackoverflow.com/questions/12033188/how-would-you-implement-your-own-reader-writer-lock-in-c11 Can someone review it - ...
3
votes
1answer
70 views

Java Concurrent Recursive API Access

I don't get to write multithreaded applications very often, so be gentle with my threads :-) I have an API input which contains a "score" and then a bunch of child nodes which also have scores, and ...
6
votes
2answers
848 views

Async Queue implementation without locking

I wrote a quick implementation of an async queue that utilizes a backing ConcurrentQueue. It was pretty much based on an implementation given in this Stack Overflow ...
4
votes
2answers
300 views

Thread-safe cache using a linked list

Are the final templated functions allocate and deallocate thread safe? The Cache object is a ...
6
votes
1answer
2k views

Getting serial port list

Needed to get a local serial port list. System.IO.Ports.SerialPort.GetPortNames() returns names but not the descriptions like you can see in Device Manager: ...
3
votes
1answer
137 views

Mutex helper for interprocess sychronization of accessing a network drive

I have two windows services working in parallel. Each of them is using a network drive that is connected and disconected dynamically by each one as required. They do it by executing ...
5
votes
2answers
125 views

Thread-Safe Garbage Collectible Memoizer

I am working on a little thread-safe, garbage collectible memoizer for Funcs in C#. The goals: Make it easy to Memoize deterministic functions. Make sure invocation of a memoized Func with a given ...
1
vote
1answer
319 views

Cached Repository that can refresh all or a subset of the data

IReadOnlyCachedRepository<T> ...
5
votes
1answer
662 views

Graceful thread shutdown with std::move [closed]

I have a thread as part of a class that access the class's data members. The class has a move constructor that moves some of the old class's data members into the new object being constructed. Before ...
4
votes
2answers
710 views

Object pool for allocating generic objects in aligned memory

I made a single header object pool for use in personal projects. It's supposed to be easy to use, cross-platform and thread safe. It uses a free list for allocations and a hashmap for dereferencing ...
6
votes
1answer
107 views

Simple time-bound cache

In my project i should cache some items (1 - 1000) in one time. Item should be removed from cache after 5 minutes by last access to cached item. Better use community libs, or standart mechanisms (...