X-Git-Url: http://git.droids-corp.org/?a=blobdiff_plain;f=doc%2Fguides%2Fprog_guide%2Fwriting_efficient_code.rst;h=d7ac6778bb4853fb0209be3a88ff44cdaa0dcfa5;hb=b95c3413fa42558df3ecd8192bc551b9564e35ea;hp=78d2afa94cda25599279da4aea6e4789e1eb46a7;hpb=29e30cbcc18ccabd134ee27b25323b468206451e;p=dpdk.git

diff --git a/doc/guides/prog_guide/writing_efficient_code.rst b/doc/guides/prog_guide/writing_efficient_code.rst
index 78d2afa94c..d7ac6778bb 100644
--- a/doc/guides/prog_guide/writing_efficient_code.rst
+++ b/doc/guides/prog_guide/writing_efficient_code.rst
@@ -105,6 +105,21 @@ meaning that if all memory access operations are done on the first channel only,
 
 By default, the  :ref:`Mempool Library <Mempool_Library>` spreads the addresses of objects among memory channels.
 
+Locking memory pages
+~~~~~~~~~~~~~~~~~~~~
+
+The underlying operating system is allowed to load/unload memory pages at its own discretion.
+These page loads could impact the performance, as the process is on hold when the kernel fetches them.
+
+To avoid these you could pre-load, and lock them into memory with the ``mlockall()`` call.
+
+.. code-block:: c
+
+    if (mlockall(MCL_CURRENT | MCL_FUTURE)) {
+        RTE_LOG(NOTICE, USER1, "mlockall() failed with error \"%s\"\n",
+                strerror(errno));
+    }
+
 Communication Between lcores
 ----------------------------
 
@@ -124,7 +139,7 @@ The code algorithm that dequeues messages may be something similar to the follow
 
     while (1) {
         /* Process as many elements as can be dequeued. */
-        count = rte_ring_dequeue_burst(ring, obj_table, MAX_BULK);
+        count = rte_ring_dequeue_burst(ring, obj_table, MAX_BULK, NULL);
         if (unlikely(count == 0))
             continue;