mdriver patch for peak util

mdriver_patch.diff

diff --git a/mymalloc/mdriver.c b/mymalloc/mdriver.c
index edbd17d..6bea5f8 100644
--- a/mymalloc/mdriver.c
+++ b/mymalloc/mdriver.c
@@ -502,6 +502,9 @@ static double eval_mm_util(const malloc_impl_t *impl, trace_t *trace, int tracen
   char *p;
   char *newp, *oldp;
▫
+  double U_numerator, U_denominator, U;
+  double peak_U = 1; // peak util: min U_numerator/U_denominator over time
+
   /* initialize the heap and the mm malloc package */
   mem_reset_brk();
   if (impl->init() < 0) {
@@ -572,13 +575,15 @@ static double eval_mm_util(const malloc_impl_t *impl, trace_t *trace, int tracen
       default:
         app_error("Nonexistent request type in eval_mm_util");
     }
+
+    U_numerator = (double)((max_total_size > MEM_ALLOWANCE) ? max_total_size : MEM_ALLOWANCE);
+    heap_size = mem_heapsize();
+    U_denominator = (double)(heap_size > MEM_ALLOWANCE ? heap_size: MEM_ALLOWANCE);
+    U = (double)U_numerator / (double)U_denominator;
+    peak_U = (U < peak_U) ? U : peak_U;
   }
-  max_total_size = (max_total_size > MEM_ALLOWANCE) ?
-    max_total_size : MEM_ALLOWANCE;
-  heap_size = mem_heapsize();
-  heap_size = (heap_size > MEM_ALLOWANCE) ?
-    heap_size : MEM_ALLOWANCE;
-  return ((double)max_total_size / (double)heap_size);
+
+  return peak_U;
 }
▫
 static void mem_op(volatile char *raddr, volatile char *waddr) {