When I was adding mlockall() to the testpmd application it was
suggested to add a reference to the use case of mlockall().
Signed-off-by: Eelco Chaudron <echau...@redhat.com>
---
doc/guides/prog_guide/writing_efficient_code.rst | 14 ++++++++++++++
1 file changed, 14 insertions(+)
diff --git a/doc/guides/prog_guide/writing_efficient_code.rst
b/doc/guides/prog_guide/writing_efficient_code.rst
index 8223aceea..3975026ce 100644
--- a/doc/guides/prog_guide/writing_efficient_code.rst
+++ b/doc/guides/prog_guide/writing_efficient_code.rst
@@ -105,6 +105,20 @@ 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
----------------------------
--
2.13.6
