disk cache modes finished

references/virtual-disk-cache-modes.xml

@@ -87,12 +87,7 @@
           guests are ignored. Using this mode implies that the user prioritizes performance gain
           over data security.
         </para>
-        <warning>
-          <para>
-            Using the <emphasis>unsafe</emphasis> mode can cause data loss in case of a host
-            failure. Do not use this mode for production workloads.
-          </para>
-        </warning>
+        <xi:include href="../snippets/unsafe-cache-mode-warning.xml"/>
       </listitem>
     </varlistentry>
     <varlistentry xml:id="cache-default">
@@ -123,7 +118,7 @@
           <para>
             This mode informs the guest of the presence of a write cache, and it relies on the
             guest to send flush commands as needed to maintain data integrity within its disk
-            image. 
+            image.
           </para>
           <warning>
             <para>
@@ -139,8 +134,9 @@
         <listitem>
           <para>
             This mode is similar to <emphasis>writeback</emphasis> caching, except the guest flush
-            commands are ignored. This means a higher risk of data loss due to host failure.
+            commands are ignored.
           </para>
+          <xi:include href="../snippets/unsafe-cache-mode-warning.xml"/>
         </listitem>
       </varlistentry>
     </variablelist>
@@ -159,16 +155,23 @@
       factors. If the guest storage is hosted on a clustered file system, is read-only, or is
       marked shareable, then the cache mode is ignored when determining if migration can be
       allowed. Otherwise, &libvirt; does not allow migration unless the cache mode is set to
-      <literal>none</literal>. However, this restriction can be overridden with the
-      <option>--unsafe</option> option to the migration APIs, which is also supported by
-      <command>virsh</command>. For example:
+      <literal>none</literal>.
     </para>
+    <warning>
+      <para>
+        If you need to do a live migration with a different cache mode than
+        <literal>none</literal>, use the <option>--unsafe</option> option, for example:
+      </para>
 <screen>&prompt.user;virsh migrate --live --unsafe</screen>
+      <para>
+        Be aware that this option may cause loss of data that the migrated VM is caching.
+      </para>
+    </warning>
     <tip>
       <para>
-        The cache mode <literal>none</literal> is required for the AIO mode setting
-        <literal>native</literal>. If another cache mode is used, the AIO mode is silently switched
-        back to the default <literal>threads</literal>.
+        When using the <literal>native</literal> asynchronous I/O mode (AIO) in &libvirt;, the
+        cache mode <literal>none</literal> is required. Using a different caching mode switches the
+        AIO mode back to the default <literal>threads</literal>.
       </para>
     </tip>
   </section>

tasks/virtual-disk-cache-mode-configure-using-virsh.xml

@@ -41,7 +41,7 @@ Id   Name       State
 <screen>&prompt.sudo;<command>virsh domblklist sle15sp5</command>
 Target   Source
 ------------------------------------------
-vda      /home/tbazant/virt/sle15.qcow2
+vda      /home/example-user/virt/sle15.qcow2
 sda      -</screen>
     </step>
     <step>
@@ -57,7 +57,7 @@ sda      -</screen>
       </para>
 <screen>&lt;disk type='file' device='disk'>
   &lt;driver name='qemu' type='qcow2' cache='writethrough'/>
-  &lt;source file='/home/tbazant/virt/sle15.qcow2'/>
+  &lt;source file='/home/example-user/virt/sle15.qcow2'/>
   &lt;target dev='vda' bus='virtio'/>
   &lt;address type='pci' domain='0x0000' bus='0x04' slot='0x00' function='0x0'/>
 &lt;/disk></screen>
@@ -77,11 +77,6 @@ sda      -</screen>
       </para>
 <screen>&prompt.sudo;<command>sudo virsh define  virt/sle15sp5.xml</command>
 Domain 'sle15sp5' defined from virt/sle15sp5.xml</screen>
-      <note>
-        <para>
-          You may have to restart a running VM for the changes to take effect.
-        </para>
-      </note>
     </step>
   </procedure>
 </topic>

tasks/virtual-disk-cache-mode-configure-using-vmm.xml

@@ -54,11 +54,6 @@
       <para>
         Confirm with <guimenu>Apply</guimenu>.
       </para>
-      <note>
-        <para>
-          You may have to restart a running VM for the changes to take effect.
-        </para>
-      </note>
     </step>
   </procedure>
 </topic>