Configuration for a particular OpenFlow table.
+
+
+
+ When is evict
, this
+ controls how flows are chosen for eviction when the flow table would
+ otherwise exceed flows. Its value is a set
+ of NXM fields or sub-fields, each of which takes one of the forms
+ field[]
or
+ field[start..end]
,
+ e.g. NXM_OF_IN_PORT[]
. Please see
+ nicira-ext.h
for a complete list of NXM field names.
+
+
+
+ When a flow must be evicted due to overflow, the flow to evict is
+ chosen through an approximation of the following algorithm:
+
-
- Maximum burst size for data received on this interface, in kb. The
- default burst size if set to 0
is 1000 kb. This value
- has no effect if
- is 0
.
-
- Specifying a larger burst size lets the algorithm be more forgiving,
- which is important for protocols like TCP that react severely to
- dropped packets. The burst size should be at least the size of the
- interface's MTU. Specifying a value that is numerically at least as
- large as 10% of helps TCP come
- closer to achieving the full rate.
-
-
-
+
+ -
+ Divide the flows in the table into groups based on the values of the
+ specified fields or subfields, so that all of the flows in a given
+ group have the same values for those fields. If a flow does not
+ specify a given field, that field's value is treated as 0.
+
-
+ -
+ Consider the flows in the largest group, that is, the group that
+ contains the greatest number of flows. If two or more groups all
+ have the same largest number of flows, consider the flows in all of
+ those groups.
+
-
- Connectivity monitor configuration for this interface.
-
+ -
+ Among the flows under consideration, choose the flow that expires
+ soonest for eviction.
+
+
-
- Key-value pairs for use by external frameworks that integrate
- with Open vSwitch, rather than by Open vSwitch itself. System
- integrators should either use the Open vSwitch development
- mailing list to coordinate on common key-value definitions, or
- choose key names that are likely to be unique. The currently
- defined common key-value pairs are:
-
- attached-mac
- -
- The MAC address programmed into the ``virtual hardware'' for this
- interface, in the form
- xx:xx:xx:xx:xx:xx.
- For Citrix XenServer, this is the value of the
MAC
- field in the VIF record for this interface.
- iface-id
- - A system-unique identifier for the interface. On XenServer,
- this will commonly be the same as
xs-vif-uuid
.
-
-
- Additionally the following key-value pairs specifically
- apply to an interface that represents a virtual Ethernet interface
- connected to a virtual machine. These key-value pairs should not be
- present for other types of interfaces. Keys whose names end
- in -uuid
have values that uniquely identify the entity
- in question. For a Citrix XenServer hypervisor, these values are
- UUIDs in RFC 4122 format. Other hypervisors may use other
- formats.
-
- The currently defined key-value pairs for XenServer are:
-
- xs-vif-uuid
- - The virtual interface associated with this interface.
- xs-network-uuid
- - The virtual network to which this interface is attached.
- xs-vm-uuid
- - The VM to which this interface belongs.
-
-
+
+ The eviction process only considers flows that have an idle timeout or
+ a hard timeout. That is, eviction never deletes permanent flows.
+ (Permanent flows do count against .
+
-
- Key-value pairs for rarely used interface features.
-
- lacp-port-priority
- - The LACP port priority of this
. In
- LACP negotiations s with numerically lower
- priorities are preferred for aggregation. Must be a number between
- 1 and 65535.
-
-
+
+ Open vSwitch ignores any invalid or unknown field specifications.
+
-
-
- Key-value pairs that report interface statistics. The current
- implementation updates these counters periodically. In the future,
- we plan to, instead, update them when an interface is created, when
- they are queried (e.g. using an OVSDB select
operation),
- and just before an interface is deleted due to virtual interface
- hot-unplug or VM shutdown, and perhaps at other times, but not on any
- regular periodic basis.
-
- The currently defined key-value pairs are listed below. These are
- the same statistics reported by OpenFlow in its struct
- ofp_port_stats
structure. If an interface does not support a
- given statistic, then that pair is omitted.
-
- -
- Successful transmit and receive counters:
-
- rx_packets
- - Number of received packets.
- rx_bytes
- - Number of received bytes.
- tx_packets
- - Number of transmitted packets.
- tx_bytes
- - Number of transmitted bytes.
-
-
- -
- Receive errors:
-
- rx_dropped
- - Number of packets dropped by RX.
- rx_frame_err
- - Number of frame alignment errors.
- rx_over_err
- - Number of packets with RX overrun.
- rx_crc_err
- - Number of CRC errors.
- rx_errors
- -
- Total number of receive errors, greater than or equal
- to the sum of the above.
-
-
-
- -
- Transmit errors:
-
- tx_dropped
- - Number of packets dropped by TX.
- collisions
- - Number of collisions.
- tx_errors
- -
- Total number of transmit errors, greater
- than or equal to the sum of the above.
-
-
-
-
-
-
+
+ When is not evict
, this
+ column has no effect.
+
+