+
+ <column name="capabilities">
+ Describes functionality supported by the hardware and software platform
+ on which this Open vSwitch is based. Clients should not modify this
+ column. See the <ref table="Capability"/> description for defined
+ capability categories and the meaning of associated
+ <ref table="Capability"/> records.
+ </column>
+
+ <column name="statistics">
+ <p>
+ Key-value pairs that report statistics about a system running an Open
+ vSwitch. These are updated periodically (currently, every 5
+ seconds). Key-value pairs that cannot be determined or that do not
+ apply to a platform are omitted.
+ </p>
+
+ <dl>
+ <dt><code>cpu</code></dt>
+ <dd>
+ <p>
+ Number of CPU processors, threads, or cores currently online and
+ available to the operating system on which Open vSwitch is
+ running, as an integer. This may be less than the number
+ installed, if some are not online or if they are not available to
+ the operating system.
+ </p>
+ <p>
+ Open vSwitch userspace processes are not multithreaded, but the
+ Linux kernel-based datapath is.
+ </p>
+ </dd>
+
+ <dt><code>load_average</code></dt>
+ <dd>
+ <p>
+ A comma-separated list of three floating-point numbers,
+ representing the system load average over the last 1, 5, and 15
+ minutes, respectively.
+ </p>
+ </dd>
+
+ <dt><code>memory</code></dt>
+ <dd>
+ <p>
+ A comma-separated list of integers, each of which represents a
+ quantity of memory in kilobytes that describes the operating
+ system on which Open vSwitch is running. In respective order,
+ these values are:
+ </p>
+
+ <ol>
+ <li>Total amount of RAM allocated to the OS.</li>
+ <li>RAM allocated to the OS that is in use.</li>
+ <li>RAM that can be flushed out to disk or otherwise discarded
+ if that space is needed for another purpose. This number is
+ necessarily less than or equal to the previous value.</li>
+ <li>Total disk space allocated for swap.</li>
+ <li>Swap space currently in use.</li>
+ </ol>
+
+ <p>
+ On Linux, all five values can be determined and are included. On
+ other operating systems, only the first two values can be
+ determined, so the list will only have two values.
+ </p>
+ </dd>
+
+ <dt><code>process_</code><var>name</var></dt>
+ <dd>
+ <p>
+ One such key-value pair will exist for each running Open vSwitch
+ daemon process, with <var>name</var> replaced by the daemon's
+ name (e.g. <code>process_ovs-vswitchd</code>). The value is a
+ comma-separated list of integers. The integers represent the
+ following, with memory measured in kilobytes and durations in
+ milliseconds:
+ </p>
+
+ <ol>
+ <li>The process's virtual memory size.</li>
+ <li>The process's resident set size.</li>
+ <li>The amount of user and system CPU time consumed by the
+ process.</li>
+ <li>The number of times that the process has crashed and been
+ automatically restarted by the monitor.</li>
+ <li>The duration since the process was started.</li>
+ <li>The duration for which the process has been running.</li>
+ </ol>
+
+ <p>
+ The interpretation of some of these values depends on whether the
+ process was started with the <option>--monitor</option>. If it
+ was not, then the crash count will always be 0 and the two
+ durations will always be the same. If <option>--monitor</option>
+ was given, then the crash count may be positive; if it is, the
+ latter duration is the amount of time since the most recent crash
+ and restart.
+ </p>
+
+ <p>
+ There will be one key-value pair for each file in Open vSwitch's
+ ``run directory'' (usually <code>/var/run/openvswitch</code>)
+ whose name ends in <code>.pid</code>, whose contents are a
+ process ID, and which is locked by a running process. The
+ <var>name</var> is taken from the pidfile's name.
+ </p>
+
+ <p>
+ Currently Open vSwitch is only able to obtain all of the above
+ detail on Linux systems. On other systems, the same key-value
+ pairs will be present but the values will always be the empty
+ string.
+ </p>
+ </dd>
+
+ <dt><code>file_systems</code></dt>
+ <dd>
+ <p>
+ A space-separated list of information on local, writable file
+ systems. Each item in the list describes one file system and
+ consists in turn of a comma-separated list of the following:
+ </p>
+
+ <ol>
+ <li>Mount point, e.g. <code>/</code> or <code>/var/log</code>.
+ Any spaces or commas in the mount point are replaced by
+ underscores.</li>
+ <li>Total size, in kilobytes, as an integer.</li>
+ <li>Amount of storage in use, in kilobytes, as an integer.</li>
+ </ol>
+
+ <p>
+ This key-value pair is omitted if there are no local, writable
+ file systems or if Open vSwitch cannot obtain the needed
+ information.
+ </p>
+ </dd>
+ </dl>
+ </column>