Amend the list of ipvs schedulers with descriptions

This PR fixes the IPVS scheduler name list by adding schedulers that
were missing and adding some descriptions (copied for source code
comments) for each.

Author: tengqm

content/en/docs/reference/networking/virtual-ips.md

@@ -207,8 +207,7 @@ _This proxy mode is only available on Linux nodes._
 In `ipvs` mode, kube-proxy watches Kubernetes Services and EndpointSlices,
 calls `netlink` interface to create IPVS rules accordingly and synchronizes
 IPVS rules with Kubernetes Services and EndpointSlices periodically.
-This control loop ensures that IPVS status matches the desired
-state.
+This control loop ensures that IPVS status matches the desired state.
 When accessing a Service, IPVS directs traffic to one of the backend Pods.
 
 The IPVS proxy mode is based on netfilter hook function that is similar to
@@ -222,12 +221,41 @@ higher throughput of network traffic.
 IPVS provides more options for balancing traffic to backend Pods;
 these are:
 
-* `rr`: round-robin
-* `lc`: least connection (smallest number of open connections)
-* `dh`: destination hashing
-* `sh`: source hashing
-* `sed`: shortest expected delay
-* `nq`: never queue
+* `rr` (Round Robin): Traffic is equally distributed amongst the backing servers.
+
+* `wrr` (Weighted Round Robin): Traffic is routed to the backing servers based on
+  the weights of the servers. Servers with higher weights receive new connections
+  and get more requests than servers with lower weights.
+
+* `lc` (Least Connection): More traffic is assigned to servers with fewer active connections.
+
+* `wlc` (Weighted Least Connection): More traffic is routed to servers with fewer connections
+  relative to their weights, that is, connections divided by weight.
+
+* `lblc` (Locality based Least Connection): Traffic for the same IP address is sent to the
+  same backing server if the server is not overloaded and available; otherwise the traffic
+  is sent to servers with fewer connections, and keep it for future assignment.
+
+* `lblcr` (Locality Based Least Connection with Replication): Traffic for the same IP
+  address is sent to the server with least connections. If all the backing servers are
+  overloaded, it picks up one with fewer connections and add it to the target set.
+  If the target set has not changed for the specified time, the most loaded server
+  is removed from the set, in order to avoid high degree of replication.
+
+* `sh` (Source Hashing): Traffic is sent to a backing server by looking up a statically
+  assigned hash table based on the source IP addresses.
+
+* `dh` (Destination Hashing): Traffic is sent to a backing server by looking up a
+  statically assigned hash table based on their destination addresses.
+
+* `sed` (Shortest Expected Delay): Traffic forwarded to a backing server with the shortest
+  expected delay. The expected delay is `(C + 1) / U` if sent to a server, where `C` is
+  the number of connections on the server and `U` is the fixed service rate (weight) of
+  the server.
+
+* `nq` (Never Queue): Traffic is sent to an idle server if there is one, instead of
+  waiting for a fast one; if all servers are busy, the algorithm falls back to the `sed`
+  behavior.
 
 {{< note >}}
 To run kube-proxy in IPVS mode, you must make IPVS available on