src/hotspot/share/gc/shenandoah/shenandoahHeapRegion.cpp

*** 800,29 ***
    return max_heap_size;
  }
  
  void ShenandoahHeapRegion::do_commit() {
    ShenandoahHeap* heap = ShenandoahHeap::heap();
!   if (!heap->is_heap_region_special() && !os::commit_memory((char *) bottom(), RegionSizeBytes, false)) {
!     report_java_out_of_memory("Unable to commit region");
    }
!   if (!heap->commit_bitmap_slice(this)) {
!     report_java_out_of_memory("Unable to commit bitmaps for region");
    }
    if (AlwaysPreTouch) {
      os::pretouch_memory(bottom(), end(), heap->pretouch_heap_page_size());
    }
    heap->increase_committed(ShenandoahHeapRegion::region_size_bytes());
  }
  
  void ShenandoahHeapRegion::do_uncommit() {
    ShenandoahHeap* heap = ShenandoahHeap::heap();
!   if (!heap->is_heap_region_special() && !os::uncommit_memory((char *) bottom(), RegionSizeBytes)) {
!     report_java_out_of_memory("Unable to uncommit region");
    }
!   if (!heap->uncommit_bitmap_slice(this)) {
!     report_java_out_of_memory("Unable to uncommit bitmaps for region");
    }
    heap->decrease_committed(ShenandoahHeapRegion::region_size_bytes());
  }
  
  void ShenandoahHeapRegion::set_state(RegionState to) {
--- 800,36 ---
    return max_heap_size;
  }
  
  void ShenandoahHeapRegion::do_commit() {
    ShenandoahHeap* heap = ShenandoahHeap::heap();
!   if (!heap->is_heap_region_special()) {
!     os::commit_memory_or_exit((char*) bottom(), RegionSizeBytes, false, "Unable to commit region");
    }
!   if (!heap->is_bitmap_region_special()) {
!     heap->commit_bitmap_slice(this);
    }
    if (AlwaysPreTouch) {
      os::pretouch_memory(bottom(), end(), heap->pretouch_heap_page_size());
    }
+   if (ZapUnusedHeapArea) {
+     SpaceMangler::mangle_region(MemRegion(bottom(), end()));
+   }
    heap->increase_committed(ShenandoahHeapRegion::region_size_bytes());
  }
  
  void ShenandoahHeapRegion::do_uncommit() {
    ShenandoahHeap* heap = ShenandoahHeap::heap();
!   if (!heap->is_heap_region_special()) {
!     bool success = os::uncommit_memory((char *) bottom(), RegionSizeBytes);
+     if (!success) {
+       log_warning(gc)("Region uncommit failed: " PTR_FORMAT " (%zu bytes)", p2i(bottom()), RegionSizeBytes);
+       assert(false, "Region uncommit should always succeed");
+     }
    }
!   if (!heap->is_bitmap_region_special()) {
!     heap->uncommit_bitmap_slice(this);
    }
    heap->decrease_committed(ShenandoahHeapRegion::region_size_bytes());
  }
  
  void ShenandoahHeapRegion::set_state(RegionState to) {