diff --git a/compiler-rt/lib/scudo/standalone/secondary.h b/compiler-rt/lib/scudo/standalone/secondary.h
--- a/compiler-rt/lib/scudo/standalone/secondary.h
+++ b/compiler-rt/lib/scudo/standalone/secondary.h
@@ -168,9 +168,8 @@
                 EntriesCount, atomic_load_relaxed(&MaxEntriesCount),
                 atomic_load_relaxed(&MaxEntrySize));
     Str->append("Stats: CacheRetrievalStats: SuccessRate: %u/%u "
-                "(%u.%02u%%)\n",
-                SuccessfulRetrieves, CallsToRetrieve,
-                Integral, Fractional);
+                "(%u.%02u%%)",
+                SuccessfulRetrieves, CallsToRetrieve, Integral, Fractional);
     for (CachedBlock Entry : Entries) {
       if (!Entry.isValid())
         continue;
@@ -544,6 +543,7 @@
   DoublyLinkedList<LargeBlock::Header> InUseBlocks GUARDED_BY(Mutex);
   uptr AllocatedBytes GUARDED_BY(Mutex) = 0;
   uptr FreedBytes GUARDED_BY(Mutex) = 0;
+  uptr FragmentedBytes GUARDED_BY(Mutex) = 0;
   uptr LargestSize GUARDED_BY(Mutex) = 0;
   u32 NumberOfAllocs GUARDED_BY(Mutex) = 0;
   u32 NumberOfFrees GUARDED_BY(Mutex) = 0;
@@ -594,6 +594,7 @@
         ScopedLock L(Mutex);
         InUseBlocks.push_back(H);
         AllocatedBytes += H->CommitSize;
+        FragmentedBytes += (reinterpret_cast<uptr>(H) - H->CommitBase);
         NumberOfAllocs++;
         Stats.add(StatAllocated, H->CommitSize);
         Stats.add(StatMapped, H->MemMap.getCapacity());
@@ -685,6 +686,7 @@
     ScopedLock L(Mutex);
     InUseBlocks.remove(H);
     FreedBytes += CommitSize;
+    FragmentedBytes -= (reinterpret_cast<uptr>(H) - H->CommitBase);
     NumberOfFrees++;
     Stats.sub(StatAllocated, CommitSize);
     Stats.sub(StatMapped, H->MemMap.getCapacity());
@@ -696,10 +698,11 @@
 void MapAllocator<Config>::getStats(ScopedString *Str) EXCLUDES(Mutex) {
   ScopedLock L(Mutex);
   Str->append("Stats: MapAllocator: allocated %u times (%zuK), freed %u times "
-              "(%zuK), remains %u (%zuK) max %zuM\n",
+              "(%zuK), remains %u (%zuK) max %zuM, Fragmented %zuK\n",
               NumberOfAllocs, AllocatedBytes >> 10, NumberOfFrees,
               FreedBytes >> 10, NumberOfAllocs - NumberOfFrees,
-              (AllocatedBytes - FreedBytes) >> 10, LargestSize >> 20);
+              (AllocatedBytes - FreedBytes) >> 10, LargestSize >> 20,
+              FragmentedBytes >> 10);
   Cache.getStats(Str);
 }