ovn: Clarify the differences between QoS marking and metering.

This also correct an error that indicated that the burst size is kbps, when it should be kb. Signed-off-by: Justin Pettit <[email protected]> Acked-by: Ben Pfaff <[email protected]>
danieldevill · Jul 6, 2018 · 8d5422b · 8d5422b
1 parent 330f6f5
commit 8d5422b
Show file tree

Hide file tree

Showing 2 changed files with 42 additions and 32 deletions.
diff --git a/ovn/northd/ovn-northd.8.xml b/ovn/northd/ovn-northd.8.xml
@@ -349,18 +349,20 @@
       </li>
     </ul>
 
-    <h3>Ingress Table 7: <code>from-lport</code> QoS marking</h3>
+    <h3>Ingress Table 7: <code>from-lport</code> QoS Marking</h3>
 
     <p>
       Logical flows in this table closely reproduce those in the
-      <code>QoS</code> table in the <code>OVN_Northbound</code> database
-      for the <code>from-lport</code> direction.
+      <code>QoS</code> table with the <code>action</code> column set in
+      the <code>OVN_Northbound</code> database for the
+      <code>from-lport</code> direction.
     </p>
 
     <ul>
       <li>
-        For every qos_rules for every logical switch a flow will be added at
-        priorities mentioned in the QoS table.
+        For every qos_rules entry in a logical switch with DSCP marking
+        enabled, a flow will be added at the priority mentioned in the
+        QoS table.
       </li>
 
       <li>
@@ -369,19 +371,20 @@
       </li>
     </ul>
 
-    <h3>Ingress Table 8: <code>from-lport</code> QoS meter</h3>
+    <h3>Ingress Table 8: <code>from-lport</code> QoS Meter</h3>
 
     <p>
       Logical flows in this table closely reproduce those in the
-      <code>QoS</code> table <code>bandwidth</code> column in the
-      <code>OVN_Northbound</code> database for the <code>from-lport</code>
-      direction.
+      <code>QoS</code> table with the  <code>bandwidth</code> column set
+      in the <code>OVN_Northbound</code> database for the
+      <code>from-lport</code> direction.
     </p>
 
     <ul>
       <li>
-        For every qos_rules for every logical switch a flow will be added at
-        priorities mentioned in the QoS table.
+        For every qos_rules entry in a logical switch with metering
+        enabled, a flow will be added at the priorirty mentioned in the
+        QoS table.
       </li>
 
       <li>
@@ -920,18 +923,18 @@ output;
       </li>
     </ul>
 
-    <h3>Egress Table 5: <code>to-lport</code> QoS marking</h3>
+    <h3>Egress Table 5: <code>to-lport</code> QoS Marking</h3>
 
     <p>
-      This is similar to ingress table <code>QoS marking</code> except for
-      <code>to-lport</code> qos rules.
+      This is similar to ingress table <code>QoS marking</code> except
+      they apply to <code>to-lport</code> QoS rules.
     </p>
 
-    <h3>Egress Table 6: <code>to-lport</code> QoS meter</h3>
+    <h3>Egress Table 6: <code>to-lport</code> QoS Meter</h3>
 
     <p>
-      This is similar to ingress table <code>QoS meter</code> except for
-      <code>to-lport</code> qos rules.
+      This is similar to ingress table <code>QoS meter</code> except
+      they apply to <code>to-lport</code> QoS rules.
     </p>
 
     <h3>Egress Table 7: Stateful</h3>

diff --git a/ovn/ovn-nb.xml b/ovn/ovn-nb.xml
@@ -122,7 +122,8 @@
     </column>
 
     <column name="qos_rules">
-      QOS marking rules that apply to packets within the logical switch.
+      QoS marking and metering rules that apply to packets within the
+      logical switch.
     </column>
 
     <column name="dns_records">
@@ -1280,19 +1281,25 @@
     </group>
   </table>
 
-  <table name="QoS" title="QOS table">
+  <table name="QoS" title="QoS table">
     <p>
-      Each row in this table represents one QOS rule for a logical switch
-      that points to it through its <ref column="qos_rules"/> column.  The <ref
-      column="action"/> column for the highest-<ref column="priority"/>
-      matching row in this table determines a packet's qos marking.  If no row
-      matches, packets will not have any qos marking.
+      Each row in this table represents one QoS rule for a logical switch
+      that points to it through its <ref column="qos_rules"/> column.
+      Two types of QoS are supported: DSCP marking and metering.  A
+      <ref column="match"/> with the highest-<ref column="priority"/>
+      will have QoS applied to it.  If the <ref column="action"/> column is
+      specified, then matching packets will have DSCP marking applied.
+      If the <ref column="bandwdith"/> column is specified, then matching
+      packets will have metering applied.  <ref column="action"/> and
+      <ref column="bandwdith"/> are not exclusive, so both marking and
+      metering by defined for the same QoS entry. If no row matches,
+      packets will not have any QoS applied.
     </p>
 
     <column name="priority">
       <p>
-        The QOS rule's priority.  Rules with numerically higher priority
-        take precedence over those with lower.  If two QOS rules with
+        The QoS rule's priority.  Rules with numerically higher priority
+        take precedence over those with lower.  If two QoS rules with
         the same priority both match, then the one actually applied to a
         packet is undefined.
       </p>
@@ -1308,7 +1315,7 @@
 
     <column name="match">
       <p>
-        The packets that the QOS rules should match, in the same expression
+        The packets that the QoS rules should match, in the same expression
         language used for the <ref column="match" table="Logical_Flow"
         db="OVN_Southbound"/> column in the OVN Southbound database's
         <ref table="Logical_Flow" db="OVN_Southbound"/> table.  The
@@ -1319,7 +1326,7 @@
     </column>
 
     <column name="action">
-      <p>The action to be performed on the matched packet</p>
+      <p>When specified, matching flows will have DSCP marking applied.</p>
       <ul>
         <li>
           <code>dscp</code>: The value of this action should be in the
@@ -1330,16 +1337,16 @@
 
     <column name="bandwidth">
       <p>
-         The bandwidth limit to be performed on the matched packet.
-         Currently only supported in the userspace by dpdk.
+         When specified, matching packets will have bandwidth metering
+         applied.  Traffic over the limit will be dropped.
       </p>
       <ul>
         <li>
           <code>rate</code>: The value of rate limit in kbps.
         </li>
         <li>
-          <code>burst</code>: The value of burst rate limit in kbps.
-          This is optional and needs to specify the <code>rate</code> first.
+          <code>burst</code>: The value of burst rate limit in kilobits.
+          This is optional and needs to specify the <code>rate</code>.
         </li>
       </ul>
     </column>