diff --git a/ChangeLog b/ChangeLog
index 836337398..81f310a91 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -23,6 +23,10 @@
 	* fix uTP edge case where udp socket buffer fills up
 	* fix nagle implementation in uTP
 
+	* fix memory allocation issue (virtual addres space waste) on windows
+
+0.16.11 release
+
 	* fix web seed URL double escape issue
 	* fix string encoding issue in alert messages
 	* fix SSL authentication issue
diff --git a/src/allocator.cpp b/src/allocator.cpp
index 2161dc38c..8268250b8 100644
--- a/src/allocator.cpp
+++ b/src/allocator.cpp
@@ -44,8 +44,8 @@ POSSIBILITY OF SUCH DAMAGE.
 #include <unistd.h> // _SC_PAGESIZE
 #endif
 
-#if TORRENT_USE_MEMALIGN || TORRENT_USE_POSIX_MEMALIGN
-#include <malloc.h> // memalign
+#if TORRENT_USE_MEMALIGN || TORRENT_USE_POSIX_MEMALIGN || defined TORRENT_WINDOWS
+#include <malloc.h> // memalign and _aligned_malloc
 #endif
 
 #ifdef TORRENT_DEBUG_BUFFERS
@@ -90,6 +90,8 @@ namespace libtorrent
 
 	char* page_aligned_allocator::malloc(size_type bytes)
 	{
+		TORRENT_ASSERT(bytes >= page_size());
+		TORRENT_ASSERT(bytes % page_size() == 0);
 #ifdef TORRENT_DEBUG_BUFFERS
 		int page = page_size();
 		int num_pages = (bytes + (page-1)) / page + 2;
@@ -115,7 +117,7 @@ namespace libtorrent
 #elif TORRENT_USE_MEMALIGN
 		return (char*)memalign(page_size(), bytes);
 #elif defined TORRENT_WINDOWS
-		return (char*)VirtualAlloc(0, bytes, MEM_COMMIT | MEM_RESERVE, PAGE_READWRITE);
+		return (char*)_aligned_malloc(bytes, page_size());
 #elif defined TORRENT_BEOS
 		void* ret = 0;
 		area_id id = create_area("", &ret, B_ANY_ADDRESS
@@ -149,7 +151,7 @@ namespace libtorrent
 #endif
 
 #ifdef TORRENT_WINDOWS
-		VirtualFree(block, 0, MEM_RELEASE);
+		_aligned_free(block);
 #elif defined TORRENT_BEOS
 		area_id id = area_for(block);
 		if (id < B_OK) return;