Merge branch 't/alsa_improvements'

diff --cc NEWS
index f50ffa3bc633ee62add70d02549f04f941e91c5c,6db7225350f014f80e3f0ad831fe60b93d2777b9..a79cc29ff044e1bd5f23b3eb5da65cb636ecad5f
--- 1/NEWS
--- 2/NEWS
+++ b/NEWS
@@@ -9,10 -9,6 +9,12 @@@
        - Shared memory areas are no longer restricted to 64K. We now
          detect the maximal size of a shared memory area at runtime.
        - cleanup of the internal uptime API.
-         communication between  para_server and para_audiod.
 +      - para_server prefaults the mmapped audio file to avoid
 +        delays on slow media.
 +      - A new test for the test-suite that exercises the
++        communication between para_server and para_audiod.
++      - The alsa writer eats up less CPU cycles when configured to
++        use the DMIX plugin.
  
  --------------------------------------
  0.4.8 (2011-08-19) "nested assignment"