Add documentation for features added a while ago.
* docs/formatdomain.html.in (Time keeping): Update documentation
of <clock> element to match 0.8.0 addition.
---
I've had this sitting on my tree for a while; any suggestions for
improvements, or should I at least check it in as-is so that we
have a start on this documentation?
docs/formatdomain.html.in | 76 ++++++++++++++++++++++++++++++++++++++++++---
1 files changed, 71 insertions(+), 5 deletions(-)
diff --git a/docs/formatdomain.html.in b/docs/formatdomain.html.in
index 5269cc5..f9a153b 100644
--- a/docs/formatdomain.html.in
+++ b/docs/formatdomain.html.in
@@ -411,13 +411,18 @@
<pre>
...
- <clock offset="localtime"/>
+ <clock offset="localtime">
+ <timer name="rtc" tickpolicy="catchup"
track="guest">
+ <catchup threshold=123 slew=120 limit=10000/>
+ </timer>
+ <timer name="pit" tickpolicy="none"/>
+ </clock>
...</pre>
<dl>
<dt><code>clock</code></dt>
<dd>
- <p>The <code>offset</code> attribute takes three possible
+ <p>The <code>offset</code> attribute takes four possible
values, allowing fine grained control over how the guest
clock is synchronized to the host. NB, not all hypervisors
support all modes.</p>
@@ -435,6 +440,7 @@
<dd>
The guest clock will be synchronized to the requested timezone
using the <code>timezone</code> attribute.
+ <span class="since">Since 0.7.7</span>
</dd>
<dt><code>variable</code></dt>
<dd>
@@ -444,14 +450,74 @@
The guest is free to adjust the RTC over time an expect
that it will be honoured at next reboot. This is in
contrast to 'utc' mode, where the RTC adjustments are
- lost at each reboot.
+ lost at each reboot. <span class="since">Since 0.7.7</span>
</dd>
</dl>
<p>
- NB, at time of writing, only QEMU supports the variable
- clock mode, or custom timezones.
+ A <code>clock</code> may have zero or more
+ <code>timer</code>sub-elements. <span class="since">Since
+ 0.8.0</span>
</p>
</dd>
+ <dt><code>timer</code></dt>
+ <dd>
+ <p>
+ Each timer element requires a <code>name</code> attribute,
+ and has other optional attributes that depend on
+ the <code>name</code> specified. Various hypervisors
+ support different combinations of attributes.
+ </p>
+ <dl>
+ <dt><code>name</code></dt>
+ <dd>
+ The <code>name</code> attribute selects which timer is
+ being modified, and can be one of "platform", "pit",
+ "rtc", "hpet", or "tsc".
+ </dd>
+ <dt><code>track</code></dt>
+ <dd>
+ The <code>track</code> attribute specifies what the timer
+ tracks, and can be "boot", "guest", or "wall".
+ Only valid for <code>name="rtc"</code>
+ or <code>name="platform"</code>.
+ </dd>
+ <dt><code>tickpolicy</code></dt>
+ <dd>
+ The <code>tickpolicy</code> attribute determines how
+ missed ticks in the guest are handled, and can be "delay",
+ "catchup", "merge", or "discard". If the policy is
+ "catchup", there can be further details in
+ the <code>catchup</code> sub-element.
+ <dl>
+ <dt><code>catchup</code></dt>
+ <dd>
+ The <code>catchup</code> element has three optional
+ attributes, each a positive integer. The attributes
+ are <code>threshold</code>, <code>slew</code>,
+ and <code>limit</code>.
+ </dd>
+ </dl>
+ </dd>
+ <dt><code>frequency</code></dt>
+ <dd>
+ The <code>frequency</code> attribute is an unsigned
+ integer specifying the frequency at
+ which <code>name="tsc"</code> runs.
+ </dd>
+ <dt><code>mode</code></dt>
+ <dd>
+ The <code>mode</code> attribute controls how
+ the <code>name="tsc"</code> timer is managed, and can be
+ "auto", "native", "emulate", "paravirt", or
"smpsafe".
+ Other timers are always emulated.
+ </dd>
+ <dt><code>present</code></dt>
+ <dd>
+ The <code>present</code> attribute can be "yes" or
"no" to
+ specify whether a particular timer is available to the guest.
+ </dd>
+ </dl>
+ </dd>
</dl>
<h3><a name="elementsDevices">Devices</a></h3>
--
1.7.2.1
Show replies by date
On 08/18/2010 12:59 AM, Eric Blake wrote:
Add documentation for features added a while ago.
* docs/formatdomain.html.in (Time keeping): Update documentation
of<clock> element to match 0.8.0 addition.
---
I've had this sitting on my tree for a while; any suggestions for
improvements, or should I at least check it in as-is so that we
have a start on this documentation?
If it's accurate, you might as well check it in right away. :)
On 08/17/2010 09:38 AM, Justin Clift wrote:
On 08/18/2010 12:59 AM, Eric Blake wrote:
> Add documentation for features added a while ago.
>
> * docs/formatdomain.html.in (Time keeping): Update documentation
> of<clock> element to match 0.8.0 addition.
> ---
>
> I've had this sitting on my tree for a while; any suggestions for
> improvements, or should I at least check it in as-is so that we
> have a start on this documentation?
If it's accurate, you might as well check it in right away. :)
Thanks; applied. For the record, here were the comments from the first
time I proposed the patch:
https://www.redhat.com/archives/libvir-list/2010-May/msg00546.html
No one found anything incorrect, per se, so much as wishing for yet more
details on the various options.
--
Eric Blake eblake(a)redhat.com +1-801-349-2682
Libvirt virtualization library
http://libvirt.org