update longhelp for vtgate

Signed-off-by: Andrew Mason <[email protected]>

go/cmd/vtgate/cli/cli.go

@@ -47,8 +47,13 @@ var (
 	Main = &cobra.Command{
 		Use:   "vtgate",
 		Short: "VTGate is a stateless proxy responsible for accepting requests from applications and routing them to the appropriate tablet server(s) for query execution. It speaks both the MySQL Protocol and a gRPC protocol.",
-		Example: `
-vtgate \
+		Long: `VTGate is a stateless proxy responsible for accepting requests from applications and routing them to the appropriate tablet server(s) for query execution. It speaks both the MySQL Protocol and a gRPC protocol.
+
+### Key Options
+` +
+			"`--srv_topo_cache_ttl`: There may be instances where you will need to increase the cached TTL from the default of 1 second to a higher number:\n" +
+			`* You may want to increase this option if you see that your topo leader goes down and keeps your queries waiting for a few seconds.`,
+		Example: `vtgate \
 	--topo_implementation etcd2 \
 	--topo_global_server_address localhost:2379 \
 	--topo_global_root /vitess/global \

go/flags/endtoend/vtgate.txt

@@ -1,4 +1,10 @@
-VTGate is a stateless proxy responsible for accepting requests from applications and routing them to the appropriate tablet server(s) for query execution. It speaks both the MySQL Protocol and a gRPC protocol.
+VTGate is a stateless proxy responsible for accepting requests from applications and routing them to the appropriate tablet server(s) for query execution.
+It speaks both the MySQL Protocol and a gRPC protocol.
+
+### Key Options
+
+* `--srv_topo_cache_ttl`: There may be instances where you will need to increase the cached TTL from the default of 1 second to a higher number:
+	* You may want to increase this option if you see that your topo leader goes down and keeps your queries waiting for a few seconds.
 
 Usage:
   vtgate [flags]