Update Xen documentation in install.rst

The Xen documentation in install.rst was out of date, describing
xm-specific changes at the point where 2.12 is mostly used with xl.
This patch removes xm-specific migration steps, references the official
Xen wiki instead of replicating information from it, removes the
VNC setup settings that are outdated for xl and probably for xm, and
slightly rewrites the documentation.

Signed-off-by: Hrvoje Ribicic <riba@google.com>
Reviewed-by: Klaus Aehlig <aehlig@google.com>

diff --git a/doc/install.rst b/doc/install.rst
index 688e9e3..9ed84ab 100644 (file)
--- a/doc/install.rst
+++ b/doc/install.rst
@@ -162,54 +162,24 @@ kernels. For KVM no reboot should be necessary.
 Xen settings
 ~~~~~~~~~~~~
 
 Xen settings
 ~~~~~~~~~~~~
 

-It's recommended that dom0 is restricted to a low amount of memory
-(512MiB or 1GiB is reasonable) and that memory ballooning is disabled in
-the file ``/etc/xen/xend-config.sxp`` by setting the value
-``dom0-min-mem`` to 0, like this::
+Depending on which toolstack you are using, the hypervisor parameter
+``xen_cmd`` has to be set to the matching value, either ``xm`` or
+``xl``.

 
 

-  (dom0-min-mem 0)
+Some useful best practices for Xen are to restrict the amount of memory
+dom0 has available, and pin the dom0 to a limited number of CPUs.
+Instructions for how to achieve this for various toolstacks can be found
+on the Xen wiki_.

 
 

-For optimum performance when running both CPU and I/O intensive
-instances, it's also recommended that the dom0 is restricted to one CPU
-only. For example you can add ``dom0_max_vcpus=1,dom0_vcpus_pin`` to your
-kernels boot command line and set ``dom0-cpus`` in
-``/etc/xen/xend-config.sxp`` like this::
+.. _wiki: http://wiki.xenproject.org/wiki/Xen_Project_Best_Practices

 
 

-  (dom0-cpus 1)
-
-It is recommended that you disable xen's automatic save of virtual
+It is recommended that you disable Xen's automatic save of virtual

 machines at system shutdown and subsequent restore of them at reboot.
 To obtain this make sure the variable ``XENDOMAINS_SAVE`` in the file
 ``/etc/default/xendomains`` is set to an empty value.
 
 machines at system shutdown and subsequent restore of them at reboot.
 To obtain this make sure the variable ``XENDOMAINS_SAVE`` in the file
 ``/etc/default/xendomains`` is set to an empty value.
 

-If you want to use live migration make sure you have, in the xen config
-file, something that allows the nodes to migrate instances between each
-other. For example:
-
-.. code-block:: text
-
-  (xend-relocation-server yes)
-  (xend-relocation-port 8002)
-  (xend-relocation-address '')
-  (xend-relocation-hosts-allow '^192\\.0\\.2\\.[0-9]+$')
-
-
-The second line assumes that the hypervisor parameter
-``migration_port`` is set 8002, otherwise modify it to match. The last
-line assumes that all your nodes have secondary IPs in the
-192.0.2.0/24 network, adjust it accordingly to your setup.
-
-If you want to run HVM instances too with Ganeti and want VNC access to
-the console of your instances, set the following two entries in
-``/etc/xen/xend-config.sxp``:
-
-.. code-block:: text
-
-  (vnc-listen '0.0.0.0') (vncpasswd '')
-
-You need to restart the Xen daemon for these settings to take effect::
-
-  $ /etc/init.d/xend restart
+You may need to restart the Xen daemon for some of these settings to
+take effect. The best way to do this depends on your distribution.

 
 Selecting the instance kernel
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
 Selecting the instance kernel
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~