Search Results

Search found 5945 results on 238 pages for 'green threads'.

Page 170/238 | < Previous Page | 166 167 168 169 170 171 172 173 174 175 176 177  | Next Page >

• How to use locks/synchronization here

  - by MasterGberry

  I have this code block here and i need to make sure the rankedPlayersWaitingForMatch is synchronized between threads properly. I was going to use synchronize but that i don't think will work here because of the variable being used in the if statement. I read online about final Lock lock = new ReentrantLock(); but I am a bit confused on how to use it in this case properly with the try/finally block. Can I get a quick example? Thanks // start synchronization if (rankedPlayersWaitingForMatch.get(rankedType).size() >= 2) { Player player1 = rankedPlayersWaitingForMatch.get(rankedType).remove(); Player player2 = rankedPlayersWaitingForMatch.get(rankedType).remove(); // end synchronization // ... I don't want this all to be synchronized, just after the first 2 remove() } else { // end synchronization // ... }

  Read the article

• Does MultiThreading in Java takes much time for task completion?

  - by Geeta

  I have to search for a string in 10 large size files (in zip format 70 MB) and have to print the lines with the search string to corresponding 10 output files.(i.e. file 1 output should be in output_file1...file2--- output_file2). The same program takes 15 mins for a single file. But if use 10 threads to read 10 files and to write in 10 different files it should complete in 15 mins but its taking 40 mins. How can I solve this. Or multithreading will take this much time only?

  Read the article

• Temporary files & folders on Windows

  - by GRIGORE-TURBODISEL

  Emulating multithreading by loading a DLL multiple times (it's designed for this). Since LoadLibrary() doesn't really allow it, the DLL copies itself into a temporary file, via GetTempPath() and GetTempFileName(). It's a small file and upon thread destruction it frees the library and deletes the temporary file. Problem now is that the number of threads is configurable (maniacs can pick 50, 100, more) which basically exposes the risk of running unstable, crash and not go through the usual "delete temporary files" routine. Is it okay if I just leave those temporary files to die there? Does the OS usually clean the up by itself? Or should I write an autocleanup routine? If yes, how can I go about saving another temporary file to hold a list with those files, and not hit UAC restrictions or otherwise? Any ideas?

  Read the article

• Are C++ Reads and Writes of an int atomic

  - by theschmitzer

  I have two threads, one updating an int and one reading it. This value is a statistic where the order of the read and write is irrelevant. My question is, do I need to synchronize access to this multi-byte value anyway? Or, put another way, can part of the write be complete and get interrupted, and then the read happen. For example, think of value = ox0000FFFF increment value to 0x00010000 Is there a time where the value looks like 0x0001FFFF that I should be worried about? Certainly the larger the type, the more possible something like this is I've always synchronized these types of accesses, but was curious what the community thought.

  Read the article

• Visually [Diagrams/movies] Display events and states of System using old logs of Application to trac

  - by singh

  Hi In My Application many process runs. Having multiple threads in each process. Whenever any bug comes, I have to analyze thousands of lines of logs to know exact root-cause. I am thinking of an idea, Please guide me if it is feasible and good enough Each log have Process name , Thread id , and Time stamp along with message. If I can create a intelligence to capture what is happing with time and display in a movie which user can view it like a normal video. Forward – backward etc. It will help to reach root cause fast and bug tracing will become easy. Please guide me on library in c++ using which I can draw diagrams and display as movie

  Read the article

• networking application and GUI in python

  - by pygabriel

  I'm writing an application that sends files over network, I want to develop a custom protocol to not limit myself in term on feature richness (http wouldn't be appropriate, the nearest thing is the bittorrent protocol maybe). I've tried with twisted, I've built a good app but there's a bug that makes my GUI blocking, so I've to switch to another framework/strategy. What do you suggest? Using raw sockets and using gtk mainloop (there are select-like functions in the toolkit) is too much difficult? It's viable running two mainloops in different threads? Asking for suggestions

  Read the article

• java statistics collection for performance evaluation

  - by user384706

  What is the most efficient way to collect and report performance statistic analysis from an application? If I have an application that uses a series of network apis, and I want to report statistics at runtime, e.g. Method doA() was called 3 times and consumed on avg 500ms Method doB() was called 5 times and consumed on avg 1200ms etc Then, I thought of using a well defined data structure (of collection) that each thread updates per remote call, and this can be used for the report. But I think that it will make the performance worse, for the time spend for statistics collection. Am I correct? How would I procceed if I used a background thread for this, and the other threads that did the remote calls were unaware of this collection gathering? Thanks

  Read the article

• Java Thread - Synchronization issue

  - by Yatendra Goel

  From Sun's tutorial: Synchronized methods enable a simple strategy for preventing thread interference and memory consistency errors: if an object is visible to more than one thread, all reads or writes to that object's variables are done through synchronized methods. (An important exception: final fields, which cannot be modified after the object is constructed, can be safely read through non-synchronized methods, once the object is constructed) This strategy is effective, but can present problems with liveness, as we'll see later in this lesson. Q1. Is the above statements mean that if an object of a class is going to be shared among multiple threads, then all instance methods of that class (except getters of final fields) should be made synchronized, since instance methods process instance variables?

  Read the article

• Why does System.Threading.Timer callback successfully update UI?

  - by Geo P

  I have several System.Threading.Timers on my form application with callbacks that update the UI...successfully - i.e. without throwing errors. I had built these earlier, before I knew that UI should not be updated on any thread other than the UI thread. Now I am confused as to why it does not throw cross-thread exceptions when I am updating UI on these separate threading.timer threads? I will be changing these callbacks so that the UI updates are invoked on UI thread, but I am curious as to why this works. Edit: My application is a WinForms Application.

  Read the article

• Which method should I use to give the perception the computer is thinking in programming?

  - by Roy

  I want to create a simple game like tic tac toe where the human user is playing against the computer. The computer function takes a couple of milliseconds to run but I would like to make the computer take 5 seconds to make a move. Which method should I use? 1) Create two memory threads. One for the computer and one for the human user. When the computer is taking 5 seconds to imitate thinking, the human user thread is paused for 5 seconds. 2) Disable input devices for 5 seconds using timer or dispatchertimer 3) Any better methods you can think of Thanks!

  Read the article

• DispatcherOperations.Wait()

  - by Mark

  What happens if you call dispatcherOperation.Wait() on an operation that has already completed? Also, the docs say that it returns a DispatcherOperationStatus, but wouldn't that always be Completed since it (supposedly) doesn't return until it's done? I was trying to use it like this: private void Update() { while (ops.Count > 0) ops.Dequeue().Wait(); } public void Add(T item) { lock (sync) { if (dispatcher.CheckAccess()) { list.Add(item); OnCollectionChanged(new NotifyCollectionChangedEventArgs(NotifyCollectionChangedAction.Add, item)); } else { ops.Enqueue(dispatcher.BeginInvoke(new Action<T>(Add), item)); } } } I'm using this in WPF, so all the Add operations have to occur on the UI thread, but I figured I could basically just queue them up without having to wait for it to switch threads, and then just call Update() before any read operations to ensure that the list is up to date, but my program started hanging.

  Read the article

• Basic QT Event handling / Threading questions ?

  - by umanga

  Greetings , I am new to QT (4.6) and have some basic questions regarding its event mechanism.I come from Swing background so I am trying to compare it with QT. 1) Does Event-processing-loop run in seperate thread? (like EventDispatch thread in Swing) ? 2) If we open several 'QMainWindow' do they run in several threads? 3) Whats the best way to run an intensive process in a seperate thread? (like SwingWorker in Swing ? ) 4) If intesive-process runs in a seperate thread ,is it possible to call UI methods like update(),repaint() from that process? thanks in advance.

  Read the article

• python unit testing os.remove fails file system

  - by hwjp

  Am doing a bit of unit testing on a function which attempts to open a new file, but should fail if the file already exists. when the function runs sucessfully, the new file is created, so i want to delete it after every test run, but it doesn't seem to be working: class MyObject_Initialisation(unittest.TestCase): def setUp(self): if os.path.exists(TEMPORARY_FILE_NAME): try: os.remove(TEMPORARY_FILE_NAME) except WindowsError: #TODO: can't figure out how to fix this... #time.sleep(3) #self.setUp() #this just loops forever pass def tearDown(self): self.setUp() any thoughts? The Windows Error thrown seems to suggest the file is in use... could it be that the tests are run in parallel threads? I've read elsewhere that it's 'bad practice' to use the filesystem in unit testing, but really? Surely there's a way around this that doesn't invole dummying the filesystem?

  Read the article

• Looking for suggestions about an architecture of a MultiThreaded app.

  - by Dimitri

  Hello everyone. I am looking to develop a multithreaded application that will be running in unconditional loop and processing high volume of data. High volume is 2000+ records per minute. Processing will involve data retrieval, calculations and data updates. I need the application to perform so that there is virtually no back log, meaning i need to be able to finish up all of the 2000 points in one minute or even faster. Our current implementation features a multithreaded application that is spawn multiple times (from 10 to 20) and we are noticing that it's not handling data as expected and i even feel that instances of the application compete with each other for processor time and eventually if not slowing, not benefiting each other for sure. I would like to know what would be the best approach: have a single instance running but maximize threads that can run simultaneously? or is there other ways i don't know? I'm open to suggestions. Thank you in advance

  Read the article

• Fast way to pass a simple java object from one thread to another

  - by Adal

  I have a callback which receives an object. I make a copy of this object, and I must pass it on to another thread for further processing. It's very important for the callback to return as fast as possible. Ideally, the callback will write the copy to some sort of lock-free container. I only have the callback called from a single thread and one processing thread. I only need to pass a bunch of doubles to the other thread, and I know the maximum number of doubles (around 40). Any ideas? I'm not very familiar with Java, so I don't know the usual ways to pass stuff between threads.

  Read the article

• Search in big text log files

  - by 0xFF

  Hi, let's say you have an game server which creating text log files of gamers actions, and from time to time you need to lookup something in those logs files (like investigating an scam or loosing an item). Just for example you have 100 files and each file have size between 20MB and 50MB - How you would search them quickly? What I have already tried to do is create several threads and each invidual thread will map his own file to memory (let say memory should not be problem if it not exceed 500MB of ram) perform search here, result was something around 1 second per file : File:a26.log - read in: 0.891, lines: 625282, matches: 78848 Is there better way how to do that ? - because it seems to me kinda slow. thanks. (java was used for this case)

  Read the article

• How can I implement a download rate limited in Java?

  - by JohnWithoutArms

  Hello, I'm going to implement a (simple) downloader application in Java as a personal exercise. It is going to run several jobs in different threads, in a way that I will be downloading a few files at the same time at all times during execution. I want to be able to define a download rate limit that is shared between all the download jobs, but I don't know how to do it even for a single download task. How should I go about doing this? What are the solutions I should try implementing? Thanks.

  Read the article

• Synchronizing access to an inner object's methods?

  - by user291701

  Suppose I have the following: public class Foo { private ReadingList mReadingList = new ReadingList(); public ReadingList getReadingList() { synchronized (mReadingList) { return mReadingList; } } } If I try modifying the ReadingList object in two threads, the synchronization above won't help me, right?: // Thread 1 foo1.getReadingList().setName("aaa"); // Thread 2 foo2.getReadingList().setName("bbb"); do I have to wrap each method I want synchronized like so: public class Foo { private ReadingList mReadingList = new ReadingList(); public synchronized void setReadingListName(String name) { mReadingList.setName(name); } public synchronized void setReadingListAuthor(String author) { mReadingList.setAuthor(author); } ... and so on for each method of ReadingList I want exposed and synched? I'd end up just writing wrapper methods for each method of ReadingList. Thanks

  Read the article

• Multithreading with STL container

  - by Steven

  I have an unordered map which stores a pointer of objects. I am not sure whether I am doing the correct thing to maintain the thread safety. typedef std::unordered_map<string, classA*>MAP1; MAP1 map1; pthread_mutex_lock(&mutexA) if(map1.find(id) != map1.end()) { pthread_mutex_unlock(&mutexA); //already exist, not adding items } else { classA* obj1 = new classA; map1[id] = obj1; obj1->obtainMutex(); //Should I create a mutex for each object so that I could obtain mutex when I am going to update fields for obj1? pthread_mutex_unlock(&mutexA); //release mutex for unordered_map so that other threads could access other object obj1->field1 = 1; performOperation(obj1); //takes some time obj1->releaseMutex(); //release mutex after updating obj1 }

  Read the article

• How to implement HeightMap smoothing using Thrust

  - by igal k

  I'm trying to implement height map smoothing using Thrust. Let's say I have a big array ( around 1 million floats). A known graphics algorithm to implement the above problem is to calculate the average around a given cell. If for example I need to calculate the value at a given cell[i,j] what I will basically do is: cell[i,j] = cell[i-1,j-1] + cell[i-1,j] + cell[i-1,j+1] + cell[i,j-1] + cell[i,j+1] + cell[i+1,j -1] + cell[i+1,j] + cell[i+1,j+1] cell[i,j] /=9 That's the CPU code. Is there a way to implement it using thrust? I know that I could use the transform algorithm. But I'm not sure it's correct to access different cells which are occupied but different threads (banks conflicts and so on).

  Read the article

• c++ thread running time

  - by chnet

  I want to know whether I can calculate the running time for each thread. I implement a multithread program in C++ using pthread. As we know, each thread will compete the CPU. Can I use clock() function to calculate the actual number of CPU clocks each thread consumes? my program looks like: Class Thread () { Start(); Run(); Computing(); }; Start() is to start multiple threads. Then each thread will run Computing function to do something. My question is how I can calculate the running time of each thread for Computing function

  Read the article

• implementing keepalives with Java

  - by Bilal

  Hi All, I am biulding a client-server application where I have to implement a keepalive mechanism in order to detect that the client has crashed or not. I have separate threads on both client and server side. the client thread sends a "ping" then sleeps for 3 seconds, while the server reads the BufferedInput Stream and checks whether ping is received, if so it makes the ping counter eqauls zero, else it increments the counter by +1, the server thread then sleeps for 3 seconds, if the ping counter reaches 3, it daclares the client as dead. The problem is that when the server reads the input stream, its a blocking call, and it blocks untill the next ping is received, irrespective of how delayed it is, so the server never detects a missed ping. any suggestions, so that I can read the current value of the stream and it doesn't block if there is nothing on the incoming stream. Thanks,

  Read the article

• ArrayBlockingQueue exceeds given capacity

  - by Wojciech Reszelewski

  I've written program solving bounded producer & consumer problem. While constructing ArrayBlockingQueue I defined capacity 100. I'm using methods take and put inside threads. And I've noticed that sometimes I see put 102 times with any take's between them. Why does it happen? Producer run method: public void run() { Object e = new Object(); while(true) { try { queue.put(e); } catch (InterruptedException w) { System.out.println("Oj, nie wyszlo, nie bij"); } System.out.println("Element added"); } } Consumer run method: public void run() { while(true) { try { queue.take(); } catch (InterruptedException e) { e.printStackTrace(); } System.out.println("Element removed"); } } Part of uniq -c on file with output: 102 Element removed 102 Element added 102 Element removed 102 Element added 102 Element removed 102 Element added 102 Element removed 102 Element added 102 Element removed 102 Element added 102 Element removed 102 Element added 2 Element removed 2 Element added 102 Element removed 102 Element added

  Read the article

• Grid computing projects similar to NGrid (thread based)

  - by DivdeAndConquer

  Hello there, first time poster. This is a great place for reading about programming problems. I've been looking at some grid computing projects for .Net/Mono and stumbled upon NGrid. NGrid seems really appealing for grid computing because you simply pass threads to it and there is very little modification you have to make to your code. However, I see that NGrid (http://ngrid.sourceforge.net/?page=overview) is still at version 0.7 and hasn't been updated since May 2008. So, I'm wondering if there are any other grid computing projects that use a similar thread-passing architecture and if anyone has had success using NGrid.

  Read the article

• why single SQL delete statement will cause deadlock?

  - by George2

  Hello everyone, I am using SQL Server 2008 Enterprise. I am wondering why even a single delete statement of this store procedure will cause deadlock if executed by multiple threads at the same time? For the delete statement, Param1 is a column of table FooTable, Param1 is a foreign key of another table (refers to another primary key clustered index column of the other table). There is no index on Param1 itself for table FooTable. FooTable has another column which is used as clustered primary key, but not Param1 column. create PROCEDURE [dbo].[FooProc] ( @Param1 int ,@Param2 int ,@Param3 int ) AS DELETE FooTable WHERE Param1 = @Param1 INSERT INTO FooTable ( Param1 ,Param2 ,Param3 ) VALUES ( @Param1 ,@Param2 ,@Param3 ) DECLARE @ID bigint SET @ID = ISNULL(@@Identity,-1) IF @ID > 0 BEGIN SELECT IdentityStr FROM FooTable WHERE ID = @ID END thanks in advance, George

  Read the article

< Previous Page | 166 167 168 169 170 171 172 173 174 175 176 177  | Next Page >