[spp] [PATCH 08/11] docs: add spp_primary in design section

[ogawa.yasufumi at lab.ntt.co.jp]

From: Yasufumi Ogawa <ogawa.yasufumi at lab.ntt.co.jp>

Add descriptions for design of spp_primary.

Signed-off-by: Yasufumi Ogawa <ogawa.yasufumi at lab.ntt.co.jp>
---
 docs/guides/overview/design.rst | 23 +++++++++++++++++++++++
 1 file changed, 23 insertions(+)

diff --git a/docs/guides/overview/design.rst b/docs/guides/overview/design.rst
index 8a7f6b7..7706488 100644
--- a/docs/guides/overview/design.rst
+++ b/docs/guides/overview/design.rst
@@ -92,6 +92,29 @@ SPP CLI is able to communicate several ``spp-ctl`` to support multiple nodes
 configuration.
 
 
+.. _spp_overview_design_spp_primary:
+
+SPP Primary
+-----------
+
+SPP is originally derived from
+`Client-Server Multi-process Example
+<https://doc.dpdk.org/guides/sample_app_ug/multi_process.html#client-server-multi-process-example>`_
+of
+`Multi-process Sample Application
+<https://doc.dpdk.org/guides/sample_app_ug/multi_process.html>`_
+in DPDK's sample applications.
+``spp_primary`` is a server process for other secondary processes and
+basically working as described in
+"How the Application Works" section of the sample application.
+
+However, there are also differences between ``spp_primary`` and
+the server process of the sample application.
+``spp_primary`` has no limitation of the number of secondary processes.
+It does not work for packet forwaring, but just provide rings and memory pools
+for secondary processes.
+
+
 Reference
 ---------
 
-- 
2.7.4