Multithreading is how work performed by a computer can be divided into multiple concurrent streams of execution (generally referred to as threads).
2
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1answer
34 views
Synchronization of remote files download
Preamble: it's a self-assigned and pure syntetic task to learn (and remember what I already knew) C# threads and synchronization and data structures.
The original question was here ...
2
votes
1answer
53 views
Dining Philosophers problem Solution with Java Reentrant Lock
I have implemented Dining Philosopher problem using ReentrantLock in java.
The goal of this program is
Every philosopher should follow the workflow of think,getchopsticks,eat,putchopsticks (No ...
1
vote
0answers
44 views
Need guidance using Tasks
I am doing multithreading using TPL Tasks first time. This is what i have done so far and I want to do it the right way. I will really appreciate if you could honor me with your expert advice.
I am ...
2
votes
1answer
65 views
Simple Freelock collection
I wrote simple lock-free collection class for saving items from multithreading code. I did it just for fun and experience. Can you check my code for potentially problems please?
public class ...
0
votes
2answers
68 views
ThreadPool implementation in C#
The following code is a self-implementation of the static class ThreadPool in C#, only the QueueUserWorkItem (the simpler method), written to practice multithreading in the .NET environment and ...
3
votes
2answers
50 views
Moving from normal threads to ExecutorService thread pools in java
I had my original threading code which worked well, but since my tasks were shortlived, I decided to use thread pools through ExecutorService.
This was my original code
public class MyRun implements ...
2
votes
2answers
29 views
Refactoring an interruptable thread
I have a long-running task that processes an input file and then uploads it to a web server. The processing part can be interrupted (with cleanup) but the upload shouldn't be interruptable so that we ...
1
vote
0answers
21 views
Uses of barriers for one main thread controlling n threads
Referring to this post: http://stackoverflow.com/questions/16328828/one-thread-controlling-many-others
My problem (summarized): One main thread waits for connections, on accept() spawns a new thread ...
0
votes
1answer
28 views
Ensuring my program is thread safe
I have a class which is responsible for waiting until a message is added to a message list and then sending it off to get processed
withdrawMessages - waits for message. I wait a total of 2 minutes ...
2
votes
0answers
21 views
Fast popcount on Intel Xeon Phi
I'm implementing an ultra fast popcount on Intel Xeon® Phi®, as it's a performance hotspot of various bioinformatics software.
I've implemented five pieces of codes,
#if defined(__MIC__)
#include ...
0
votes
0answers
8 views
How do you have threads in Ruby send strings back to a parent thread [migrated]
I want to be able to call a method that repeats x amount of times on a separate thread that sends messages such as "still running" every few moments to the console while I am free to call other ...
2
votes
0answers
37 views
Monkey testing a SmartCard library
My definition of monkey testing is basically playing with a program in as if I was a monkey (press every button, unplug things, go in the wrong order..etc etc)
So I made a rather simple SmartCard ...
2
votes
1answer
95 views
Review of simple Java Actor library
How can I improve this code?
Also available from git://github.com/edescourtis/actor.git .
Actor.java
package com.benbria.actor;
public interface Actor<T> extends Runnable {
public ...
-1
votes
0answers
84 views
What is needed to bring the website down?
I am running windows 7 (32 OS),on intel core 2 duo processor and 4 GB RAM. For learning purposes I was trying a Spam attack on a local website with the code written in java. I started the application ...
3
votes
2answers
54 views
Is this a scenario to use volatile instead of synchronized?
I want to know if using volatile in this scenario will give a better performance than using synchronization. Specifically for the paused and running instance variable in the SimulationManager class.
...
2
votes
1answer
80 views
parallel_for_each
I have constructed a simple implementation of a parallel loop.
#include <algorithm>
#include <thread>
#include "stdqueue.h"
namespace Wide {
namespace Concurrency {
...
1
vote
1answer
46 views
Java - Is this the correct implementation of a timer/timertask to destroy a process that overruns a defined time limit
I was wondering if this is the correct implementation of a times task to destroy a thread after it overruns a predefined time period:
it works by creating a getting the thread from ...
0
votes
1answer
56 views
Java concurrent Map of List
I need concurrent HashMap of List as value with following behavior:
count of read/write ops approximately equals
support add/remove values in lists
thread safe iterations over lists
After some ...
4
votes
2answers
141 views
Java HTTP Server and multi-threading optimization
I wrote an http server for the management of scores for users and levels.
It can returns the highest score per level.
It has a simple login with session-key.
What do you think could be improved in ...
2
votes
0answers
266 views
Lock-free multiple-consumer multiple-producer queue
The code below implements an intrusive lock-free queue that supports multiple concurrent producers and consumers.
Some features:
Producers and consumers work on separate ends of the queue most of ...
1
vote
0answers
32 views
Communication with GARMIN throught WEB (Java Socket Programming Code Review)
I am developing a WEB based GPS system and one of its functionallity is to be able to send messages and routes to GARMIN devices.
I have never been using sockets before and for some (obvious) reason ...
0
votes
1answer
45 views
Does refactoring a while loop increase CPU usage
While upgrading our code base to take advantage of new features in .Net 4.5, I'm trying to refactor our take of the classic Producer/Consumer algorithm, but I'm concerned my refactoring is going to ...
0
votes
1answer
87 views
Multi Threaded Error Logger
I am trying to design a class that will log errors to a text file, the application is using threads heavily so it may be that 2 errors that need to be written at the same time. I know there are 3rd ...
3
votes
1answer
107 views
Multi threaded circular buffer
I should write a circular buffer with multithread write and single read ability. Here is my solution:
public class RingBuffer<E> extends AbstractList<E> implements RandomAccess {
...
1
vote
1answer
144 views
How to update my Swing JTable dynamically. MVC Pattern
I have created a program using a version of MVC architecture. The purpose of the code is to scrape the h1 titles of a list of webpages and to return the results to a JTable.
So far I have the ...
1
vote
1answer
77 views
creating dynamic threads
First, I want to say that this code works, but I want to make sure this is the right way of doing it. I am writing this for a SMS text API that loops through each phone number. I sometimes gets hung ...
3
votes
1answer
67 views
Implementation of ordered lock pattern
Below is attempt to catch potential deadlocks at runtime in C#. Basically this class allows user to acquire locks in a pre-defined order only. I ran some basic tests and it appears to work. Please ...
0
votes
0answers
55 views
Haskell network connection graceful handler
Just trying to work out some simple graceful connection handling code in Haskell to get my head around some of the IO/Networking/Threading stuff, some tips where I'm doing things poorly would be ...
1
vote
2answers
78 views
Multi-threaded Winforms Conventions for Main()
I'm trying to find a good pattern for new applications (and for refactoring old ones).
Maybe it's just me, but I dislike spawning my main logic thread from inside my main form thread (so far I always ...
0
votes
1answer
85 views
Asynchronous version of AutoResetEvent
This is my second attempt to create asynchronous version of AutoResetEvent.
At first I tried to make it completely lock-less, but it turned out to be impossible.
This implementation contains a lock ...
3
votes
1answer
186 views
Java thread safety and caching techniques
This is my first Java multi-threading code. It is part of an Android application that is a client to a webpage that serves books. Each page of the book is in a separate PDF, and the Book class ...
0
votes
0answers
55 views
Finding Potential Thread Safety issues and Race conditions in my Multithreading Code
I am working on a project in which I have two tables in a different database with different schemas. So that means I have two different connection parameters for those two tables to connect using ...
1
vote
1answer
50 views
Log and Count the exception in a Single method
I am tring to count the number of exceptions happening and log those exceptions as well. So what I did is, I created one method addException in which I am counting all the exceptions.
addException ...
1
vote
1answer
63 views
Looping through the ResultSet efficiently and the add the values for columns in List<String>
I am working on a multithreaded project in which each thread will randomly find columns for that table and I will be using those columns in my SELECT sql query and then I will be executing that SELECT ...
1
vote
1answer
162 views
Producer/Consumer with some limitations
The code realizes producer/consumer problem with multiple producers and consumers. Have this code any potential deadlock or races?
//RandomDataProvider.cs
namespace MyNamespace.Core
{
using ...
2
votes
4answers
151 views
Designing a better logger class
Could you please critisize the logger class below? Can it be used in a multi threaded web environment? If not how can I improve it? Is there anything wrong with locking in WriteToLog method or ...
3
votes
1answer
99 views
Thread Safety issues in the multithreading code
I am working on a project in which I have two tables in a different database with different schemas. So that means I have two different connection parameters for those two tables to connect using ...
3
votes
1answer
854 views
Java multithreaded file server and client. Emulate TCP over UDP
This is for homework.
My task was similar to my last assignment but this time I had to do it with UDP instead of TCP. This basically means I had to emulate TCP over UDP.
Multithreading was an ...
1
vote
2answers
122 views
Does my main class have too much code?
For some reason i have the feeling that i should put all of my thread starts and joins in a for loop just to reduce the amount of code. I dunno if that will hurt readability on this class? Also is it ...
2
votes
1answer
131 views
Lock free MPMC Ring buffer implementation in C
I have written a lock free MPMC FIFO in C based on a ring buffer. It uses gcc's atomic built-ins to achieve thread safety. The queue is designed to return -1 if it's full on enqueue or empty on ...
1
vote
2answers
69 views
Correct implementation for background task execution in web application?
I have a simple servlet which merely serves some cached data back to the user. I also have a background thread which runs at fixed intervals to refresh the cached data. Is this a reasonable ...
2
votes
0answers
43 views
Is this a correct way to handle a thread which uses a socket?
I am building an app for android to control VLC (mediaplayer) that runs on my computer.
Atm it's just a prototype and it works but I was wondering if I am correctly managing my HandlerThread and ...
3
votes
2answers
158 views
Multi-threaded sort
I wanted to write a multi-threaded sort, unfortunately I don't know much about threads, especially in C++11. I managed to make something work, but I would be highly surprised if it was the best way to ...
4
votes
1answer
51 views
Timing single operation to not be repeated for a fixed time
Sometimes "a" service does not respond and so we need to restart it. Usually it's a glitch in the network. We can have like 100 calls at the same time so the service cannot be restarted for 100 ...
2
votes
1answer
129 views
Simple ThreadSafe Log Class
For the m_listeners BlockingCollection<>, I know it's a bit hacky right now, but I'm not sure what to use instead (List<>, Dictionary<>, something else?). I want to be able to add/remove ...
1
vote
1answer
43 views
Alternative to using sleep() to avoid a race condition in PyQt
I have a situation where I would like to use a single QThread to run two (or more) separate methods at different times. For example, I would like the QThread to run play() sometimes, and when I am ...
0
votes
3answers
64 views
How to correctly get a IDisposeable when you need to lock the factory?
If I need to create a IDisposeable object from a factory, but if the factory object is not thread safe and requires me to lock on it is this the correct pattern to use?
public void ...
4
votes
2answers
112 views
Getting a decryptor object
I need to lock on my AesManaged instance _Aes to call CreateDecryptor() however the CreateDecryptor() method is not thread safe and this function could be called by multiple threads. Is this the ...
2
votes
2answers
85 views
Simple FIFO Job list in Java
For the first time I have to play with Threads in java.
Basically, my code is a simple FIFO job queue.
The main thread regularly puts jobs in the queue wich need to be executed.
The code below is a ...
2
votes
1answer
50 views
Of the good usage of rhino
This is a sample class using Rhino (1.7R4). I need it because in the context of JSON Schema, regexes should be ECMA 262. One requirement is that it is thread safe, and it is.
But I'm not sure I ...
