Update comment

m-buffer.h

@@ -312,9 +312,13 @@ M_C(name, _init)(buffer_t v, size_t size)                               \
 /* Definition of a a QUEUE for Many Produccer / Many Consummer
    for high bandwidth scenario:
    * lock-free,
-   * wait-free but only because it accept to fail spuriously,
+   * wait-free but only because it accepts to fail spuriously,
    * quite fast
-   * no blocking calls.  */
+   * no blocking calls.
+   * only queue (no stack)
+   * size of queue is always a power of 2
+   * no overwriting.
+   */
 
 #define QUEUEI_MPMC_DEF2(name, type, policy, oplist, buffer_t)		\
 									\