diff --git a/ChangeLog b/ChangeLog
index 65ce1c155..4ffc7267c 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,4 @@
+	* optimized the torrent creator optimizer to scale significantly better with more files
 	* fix uTP edge case where udp socket buffer fills up
 	* fix nagle implementation in uTP
 
diff --git a/src/file_storage.cpp b/src/file_storage.cpp
index c59d286ef..f07deaee9 100644
--- a/src/file_storage.cpp
+++ b/src/file_storage.cpp
@@ -494,43 +494,24 @@ namespace libtorrent
 		TORRENT_ASSERT(dst < int(m_files.size()));
 		TORRENT_ASSERT(dst < index);
 
-		internal_file_entry e = m_files[index];
-		m_files.erase(m_files.begin() + index);
-		m_files.insert(m_files.begin() + dst, e);
+		std::iter_swap(m_files.begin() + index, m_files.begin() + dst);
 		if (!m_mtime.empty())
 		{
 			TORRENT_ASSERT(m_mtime.size() == m_files.size());
-			time_t mtime = 0;
-			if (int(m_mtime.size()) > index)
-			{
-				mtime = m_mtime[index];
-				m_mtime.erase(m_mtime.begin() + index);
-			}
-			if (dst > int(m_mtime.size())) m_mtime.resize(dst, 0);
-			m_mtime.insert(m_mtime.begin() + dst, mtime);
+			if (int(m_mtime.size()) < index) m_mtime.resize(index+1, 0);
+			std::iter_swap(m_mtime.begin() + dst, m_mtime.begin() + index);
 		}
 		if (!m_file_hashes.empty())
 		{
 			TORRENT_ASSERT(m_file_hashes.size() == m_files.size());
-			char const* fh = 0;
-			if (int(m_file_hashes.size()) > index)
-			{
-				fh = m_file_hashes[index];
-				m_file_hashes.erase(m_file_hashes.begin() + index);
-			}
-			if (int(m_file_hashes.size()) < dst) m_file_hashes.resize(dst, NULL);
-			m_file_hashes.insert(m_file_hashes.begin() + dst, fh);
+			if (int(m_file_hashes.size()) < index) m_file_hashes.resize(index + 1, NULL);
+			std::iter_swap(m_file_hashes.begin() + dst, m_file_hashes.begin() + index);
 		}
 		if (!m_file_base.empty())
 		{
 			TORRENT_ASSERT(m_file_base.size() == m_files.size());
-			size_type base = 0;
-			if (int(m_file_base.size()) > index)
-			{
-				base = m_file_base[index];
-				m_file_base.erase(m_file_base.begin() + index);
-			}
-			m_file_base.insert(m_file_base.begin() + dst, base);
+			if (int(m_file_base.size()) < index) m_file_base.resize(index + 1, NULL);
+			std::iter_swap(m_file_base.begin() + dst, m_file_base.begin() + index);
 		}
 	}
 
@@ -608,27 +589,31 @@ namespace libtorrent
 				// note that i will be set to point to the
 				// new pad file. Once we're done adding it, we need
 				// to increment i to point to the current file again
-				internal_file_entry e;
+				// first add the pad file to the end of the file list
+				// then swap it in place. This minimizes the amount
+				// of copying of internal_file_entry, which is somewhat
+				// expensive (until we have move semantics)
 				int cur_index = file_index(*i);
-				i = m_files.insert(i, e);
-				i->size = pad_size;
-				i->offset = off;
+				int index = m_files.size();
+				m_files.push_back(internal_file_entry());
+				internal_file_entry& e = m_files.back();
+				// i may have been invalidated, refresh it
+				i = m_files.begin() + cur_index;
+				e.size = pad_size;
+				e.offset = off;
 				char name[30];
 				snprintf(name, sizeof(name), ".____padding_file/%d", padding_file);
 				std::string path = combine_path(m_name, name);
-				i->set_name(path.c_str());
-				i->pad_file = true;
+				e.set_name(path.c_str());
+				e.pad_file = true;
 				off += pad_size;
 				++padding_file;
 
-				if (int(m_mtime.size()) > cur_index)
-					m_mtime.insert(m_mtime.begin() + cur_index, 0);
+				if (!m_mtime.empty()) m_mtime.resize(index + 1, 0);
+				if (!m_file_hashes.empty()) m_file_hashes.resize(index + 1, NULL);
+				if (!m_file_base.empty()) m_file_base.resize(index + 1, 0);
 
-				if (int(m_file_hashes.size()) > cur_index)
-					m_file_hashes.insert(m_file_hashes.begin() + cur_index, NULL);
-
-				if (int(m_file_base.size()) > cur_index)
-					m_file_base.insert(m_file_base.begin() + cur_index, 0);
+				reorder_file(index, cur_index);
 
 				// skip the pad file we just added and point
 				// at the current file again