Re: New to D - playing with Thread and false Sharing

[tony288 via Digitalmars-d-learn]

On Thursday, 20 August 2015 at 15:37:35 UTC, Dejan Lekic wrote:
Keep in mind that in D everything is thread-local by default! :)
For shared resources use __gshared or shared (although I do not 
know for sure whether shared works or not).

Thanks, I changed the code and the previous one was already using 
shared.
import std.stdio;
import core.time;
import core.thread;

void main() {
                MonoTime before =  MonoTime.currTime;
                 runTest();
                MonoTime after = MonoTime.currTime;
                Duration timeElapsed = after - before;
                writeln("Duration is " , timeElapsed) ;


}       

    private static void runTest()
    {
        Thread[] threads = new Thread[4];
        FalseSharing[] fs = new FalseSharing[4];

        for (int i = 0; i < threads.length; i++){
                FalseSharing fsx = new FalseSharing(i);
            fs[i] = fsx;
                        threads[i] = fsx;
                        }
                foreach(Thread t ; threads){//starts all threads
            t.start();
            }
                foreach(Thread t; threads){
                        t.join();
                }


    }
        static PaddingClass[] longs = new PaddingClass[4];

        class FalseSharing : Thread
        {
            private const int threadIndex;
            this(const int index)
            {
                threadIndex = index;
                longs[threadIndex] = new PaddingClass();
                super(&run);
            }
            void run()
            {   
                long max = 1000L * 100L * 100L * 10L;
	        for(long i=1; i<=max ; i++){longs[threadIndex].value = 
i;}
            }

        }
        public static shared class PaddingClass
        {
            public double p1,p2,p3,p4,p5,p6;//padding.
	    public shared long value = 0L; //shared across multiple 
thread
        }

So what I see, D ( of course and expected) using more or less the 
same syntax as java. Behaves very differently. Which I mean 
padding or not, D behaves slower than Java with padding by a long 
way.

Now what I would like to know, how would I make this code more 
efficient? Which is basically the aim I'm trying to achieve.

Any pointers would be really help full. Should I use 
concurrency/parallelism etc..?

Thanks