diff -r 8d3932671e48 Lib/shutil.py
--- a/Lib/shutil.py	Wed Oct 28 21:45:01 2015 +0200
+++ b/Lib/shutil.py	Thu Oct 29 00:38:08 2015 +0100
@@ -113,7 +113,16 @@
     else:
         with open(src, 'rb') as fsrc:
             with open(dst, 'wb') as fdst:
-                copyfileobj(fsrc, fdst)
+                if hasattr(os, 'sendfile'):
+                    # Prefer os.sendfile if available for performance
+                    max_bcount = 2 ** 31 - 1
+                    bcount = max_bcount
+                    offset = 0
+                    while bcount > 0:
+                        bcount = os.sendfile(fdst.fileno(), fsrc.fileno(), offset, max_bcount)
+                        offset += bcount
+                else:
+                    copyfileobj(fsrc, fdst)
     return dst
 
 def copymode(src, dst, *, follow_symlinks=True):