[3.0] 7e0bcc1 Add section on transparent hugepages. Move virtualised into platformnotes

[Lasse Karstensen]

commit 7e0bcc1eff27572d8d10b0abe8507bce186b9e6a
Author: Lasse Karstensen <lasse at varnish-software.com>
Date:   Thu Nov 22 13:57:57 2012 +0100

    Add section on transparent hugepages. Move virtualised into platformnotes

diff --git a/doc/sphinx/tutorial/platformnotes.rst b/doc/sphinx/tutorial/platformnotes.rst
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+
+Platform specific notes
+------------------------
+
+Transparent hugepages on Redhat Linux 6
+~~~~~~~~~~~~
+
+On RHEL6 Transparent Hugepage kernel support is enabled by default.
+This is known to cause sporadic crashes of Varnish.
+
+It is recommended to disable transparent hugepages on affected systems:
+
+    $ echo "never" > /sys/kernel/mm/redhat_transparent_hugepage/enabled
+
+On Debian/Ubuntu systems running 3.2 kernels the value is "madvise", which does
+not need to be changed.
+
+
+OpenVZ
+~~~~~~
+
+It is possible, but not recommended for high performance, to run
+Varnish on virtualised hardware. Reduced disk and network -performance
+will reduce the performance a bit so make sure your system has good IO
+performance.
+
+If you are running on 64bit OpenVZ (or Parallels VPS), you must reduce
+the maximum stack size before starting Varnish.
+
+The default allocates to much memory per thread, which will make varnish fail
+as soon as the number of threads (traffic) increases.
+
+Reduce the maximum stack size by running::
+
+    ulimit -s 256
+
+in the Varnish startup script.
+
diff --git a/doc/sphinx/tutorial/virtualised.rst b/doc/sphinx/tutorial/virtualised.rst
deleted file mode 100644
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-
-Running Varnish in a virtualized environment
---------------------------------------------
-
-It is possible, but not recommended for high performance, to run
-Varnish on virtualised hardware. Reduced disk- and network performance
-will reduce the performance a bit so make sure your system has good IO
-performance.
-
-OpenVZ
-~~~~~~
-
-If you are running on 64bit OpenVZ (or Parallels VPS), you must reduce
-the maximum stack size before starting Varnish. The default allocates
-to much memory per thread, which will make varnish fail as soon as the
-number of threads (==traffic) increases.
-
-Reduce the maximum stack size by running::
-
-    ulimit -s 256
-
-in the startup script.
-