set default values for community filter cutoff and query limit

etc/alice-lg/alice.example.conf

@@ -43,7 +43,7 @@ neighbors_store_refresh_interval = 5
 # Maximum number of routes returned from the store in a prefix
 # search, to avoid timeouts with too big result sets.
 # This is important when querying BGP communities, as some might
-# match a large number of routes.
+# match a large number of routes. (Default: 200000)
 routes_store_query_limit = 200000
 
 # Add a delay to the stream parser in order to reduce

pkg/config/config.go

@@ -74,6 +74,10 @@ const (
 	// routes after which the community filter will not be
 	// available.
 	DefaultPrefixLookupCommunityFilterCutoff = 100000
+
+	// DefaultRoutesStoreQueryLimit is the default limit for
+	// prefixes returned from the store.
+	DefaultRoutesStoreQueryLimit = 200000
 )
 
 // A ServerConfig holds the runtime configuration
@@ -940,6 +944,7 @@ func LoadConfig(file string) (*Config, error) {
 		StoreBackend:                      "memory",
 		RoutesStoreRefreshParallelism:     1,
 		NeighborsStoreRefreshParallelism:  1,
+		RoutesStoreQueryLimit:             DefaultRoutesStoreQueryLimit,
 	}
 	if err := parsedConfig.Section("server").MapTo(&server); err != nil {
 		return nil, err