The WeakReference class, monitoring memory leak and garbage collection in a Java application

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 Below is a Stack implementation that uses an internal resizeable array structure.  public class MyStack< T > implements Stack< T > { private static final int CAPACITY = 100 ; private Object[] array ; private int pos = 0 ; public MyStack () { this . array = new Object[ CAPACITY ] ; } @Override public void push ( T item) { if ( pos >= array . length / 2 ) { Object[] newArray = new Object[ pos * 2 ] ; System. arraycopy ( array , 0 , newArray , 0 , array . length ) ; array = newArray ; } array [ pos ++] = item ; } @Override public T pop () { if (isEmpty()) { throw new RuntimeException( "empty stack" ) ; } @SuppressWarnings ( "unchecked" ) T item = ( T ) array [ pos - 1 ] ; pos -= 1 ; return item ; } @Override @SuppressWarnings ( "unchecked" ) public T peek...
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SimpleScalar Simulator - Part 3

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Problem: Can you detect when current page is left for the instruction stream?

Inside cache.c we know if the hit is fast (same block) or slow.

/*cache.c  line 533*/
printf("Cache tagset: %d  Last tagset: %d\n", CACHE_TAGSET(cp, addr), cp->last_tagset);

   /* check for a fast hit: access to same block */
  if (CACHE_TAGSET(cp, addr) == cp->last_tagset)
    {

       printf("Same block hit!\n");

       /* hit in the same block */
      blk = cp->last_blk;
      goto cache_fast_hit;
    }

 printf("Slow hit or miss!\n");

Before cache access, we control the nature of the access and set the iTLB power mode:

          if (itlb)
  {

    if (CACHE_TAGSET(itlb, IACOMPRESS(fetch_regs_PC)) == itlb->last_tagset) {
       low_power = 1;
       ++low_power_count;
   } else {
                low_power = 0;
                ++normal_power_count;
   }

    printf("Low count = %d, normal count = %d\n", low_power_count, normal_power_count);

             printf("Low power ratio: %f\n", (double)low_power_count / (low_power_count + normal_power_count));

      /* access the I-TLB*/
     tlb_lat = cache_access(itlb, Read, IACOMPRESS(fetch_regs_PC), NULL, ISCOMPRESS(sizeof(md_inst_t)), sim_cycle, NULL, NULL);
  
printf("Address is: %d  Size is: %d  Cycle is: %d\n", IACOMPRESS(fetch_regs_PC), ISCOMPRESS(sizeof(md_inst_t)), sim_cycle);

After running my hello.c program, the result is:

Low count = 9010, normal count = 159
Low power ratio: 0.982659



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