evaluate different webservers

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diff --git a/docs/system/overview.rst b/docs/system/overview.rst
index 00e439f45..09e3bc857 100755
--- a/docs/system/overview.rst
+++ b/docs/system/overview.rst
@@ -20,6 +20,7 @@ In this section you will find information and diagrams to better understand the
 
     plugin_hierarchy.rst
     hoster_diagrams.rst
+    webserver_evaluation.rst
 
 
 .. rubric:: Footnotes
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diff --git a/docs/system/webserver_evaluation.rst b/docs/system/webserver_evaluation.rst
new file mode 100644
index 000000000..2dc8d3265
--- /dev/null
+++ b/docs/system/webserver_evaluation.rst
@@ -0,0 +1,85 @@
+.. _webserver_evaluation:
+
+====================
+Webserver Evaluation
+====================
+
+pyLoad supports all kind of webserver that are usable with bottle.py [1]_.
+For this reason we evaluted each of them to find the ones that are worth to be supported in pyLoad. The results of this
+evaluation make sure pyload can select the most suited webserver with its auto selecting algorithm.
+
+First selection
+---------------
+
+The first step was to take a short look at every webserver. For some it was not needed to further inspect them,
+since they don't meet our requirements.
+
+================== ===============================================================
+Disregarded server Reason
+================== ===============================================================
+paste              threaded server, no improvement to bundled one
+twisted            Too heavy (30 MB RAM min), far more complex as what we need
+diesel             Problems with setup, no default packages, Not working in tests
+gunicorn           Preforking server, messes many things up in our use-case
+gevent             Not usuable with several threads
+gae                Google App Engine, not for personal maschines
+rocket             threaded server, seems not better than bundled one
+================== ===============================================================
+
+pyLoad has an threaded server bundled itself. All threaded server that were tested seems not better than this
+implementation and thus were not further benchmarked. "flup", known as "fastcgi" in pyload, serves a different
+use-case and is not taken into consideration here.
+
+Comparision
+-----------
+
+The remaining servers, were evaluated for different criteria. We ran the following benchmark with different options:
+
+    ab -n 15000 -c 1 http://127.0.0.1:8001/login
+
+This benchmark was ran with -c 1, -c 5, as well as -k option to test performance with more concurrency and keep-alive
+feature, we use time per request (mean, across all concurrent requests) for comparision.
+
+Additionally we collected RAM usage statistic before (b.) (only 2-3 pages retrieved) and after (a.) the benchmarks were run.
+The comparision also includes some notes and available packages or features, especially SSL is of interest.
+
+========== ======== ======== ====== ====== ======= ======= === ============= ================================
+Server     RAM (b.) RAM (a.) -c 1   -c 5   -c 1 -k -c 5 -k SSL Packages      Notes
+========== ======== ======== ====== ====== ======= ======= === ============= ================================
+wsgiref    21.7     22.6     1.240  1.179  1.312   1.513   No  Included
+threaded   25.5     28.0     0.912  1.139  0.656   0.784   Yes Included
+tornado    23.8     25.9     0.874  0.935  -       -       Yes mac,deb,arch
+fapws3     22.3     23.8     0.740  0.733  0.786   0.594   No  pip           Very reliable under load,
+                                                                             problem with shutdown, will
+                                                                             need patches for integration
+meinheld   22.3     23.7     0.622  1.001  1.076   1.388   Yes pip           Segfaults when shutdown
+eventlet   25.0     26.0     1.021  1.031  0.755   0.740   Yes mac,deb       Struggles a bit under load
+                                                                             More ram with -k (27.6)
+
+bjoern     21.7     23       0.623  1.062  -       -       No  git           memory-leak with faulty -k
+========== ======== ======== ====== ====== ======= ======= === ============= ================================
+
+"wsgiref" is a standard implementation shipped with python and within pyLoad known as builtin.
+"threaded" is taken from cherryPy and also included with pyLoad.
+The keep-alive implementation of "ab" is not 100% compliant, some server struggle with it.
+
+Conclusion
+----------
+
+The wsgiref server is known to show strange performance on some system and is therefore not selected by default anymore.
+The included threaded server has all needed functions, including SSL, and is usable without any other packages.
+Threaded will be selected in case none of the other server is installed.
+
+Our auto-select will favor RAM usage over performance too choose the most lightweight server as possible.
+Activating SSL will decrease the options, many lightweight servers don't include SSL by choice.
+They suggest tools like pound [2]_, stunnel [3]_, or any other reverse proxy capable server. Also these that are capable
+of SSL suggest using other tools, their SSL performance was not tested here.
+
+pyLoad will select a server in following order:
+fapws3 -> meinheld -> bjoern -> tornado -> eventlet
+
+.. rubric:: Footnotes
+
+.. [1] https://bitbucket.org/spoob/pyload/src/127adb41465712548949ea872a5453e4b0b0fbb8/module/lib/bottle.py?at=default#cl-2555
+.. [2] http://www.apsis.ch/pound/
+.. [3] https://www.stunnel.org/index.html
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