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Thread: Memory usage increasing in while loop - is it a memory leak

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    Default Memory usage increasing in while loop - is it a memory leak

    Hi

    I have the following bit of code, basically keeps getting a list of available Drives on a windows computer (every 2 seconds at the moment but it will be every 30secs).

    Trouble is that when running this when watching the memory usage in Task Manager the memory keeps increasing, I have left this running for around 10 minutes and it still increasing.

    Is there any reason why this is happening as it SHOULD be just replacing the contents of 'currentDrives' variable.

    Thanks

    import java.io.File;
     
    public class Main {
     
     
        public static void main(String[] args)
        {
            File[] currentDrives = File.listRoots();
     
            while(true)
            {
                currentDrives = File.listRoots();
     
                try
                {
                    Thread.sleep(2000);
                }
                catch(Exception ex)
                {
                    System.out.println("Error: " + ex.getMessage());
                }
            }
     
        }
     
    }


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    Default Re: Memory usage increasing in while loop - is it a memory leak

    Trouble is that when running this when watching the memory usage in Task Manager the memory keeps increasing, I have left this running for around 10 minutes and it still increasing
    Does it ever throw an out of memory exception? If not, then I wouldn't worry. A variable that is out of scope with no more references means it is eligible for garbage collection, but does not mean it is immediately garbage collected. If this were how the garbage collector worked, it would add massive overhead to an application.
    See http://java.sun.com/docs/books/perfo...PAppGC.fm.html

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    Default Re: Memory usage increasing in while loop - is it a memory leak

    Thanks very much, it has been running around 30 minutes now and it seems to have stopped increasing the memory usage, it starts off at around 7mb and has stopped increasing around 12.6mb and has been solid there for around 5 minutes now.

    Thanks again

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