changes to nodeDB size and a comment

meshtastic/deviceonly.options

@@ -2,8 +2,12 @@
 # https://jpa.kapsi.fi/nanopb/docs/reference.html#proto-file-options
 
 # FIXME pick a higher number someday? or do dynamic alloc in nanopb?
-*DeviceState.node_db max_count:40
-*DeviceState.node_db_neighbors max_count: 40
+# As of April 2023, the size of a NodeInfo packet is approx. 130 bytes. We previously
+# capped storage at 80 such packets. The size of a Neighbor is 12 bytes, meaning we can fit
+# 10 for every NodeInfo. Thus, our footprint for storing 20 Neighbors in the DB is a little under
+# 2 NodeInfo.
+*DeviceState.node_db max_count:78
+*DeviceState.node_db_neighbors max_count:20
 
 # FIXME - max_count is actually 32 but we save/load this as one long string of preencoded MeshPacket bytes - not a big array in RAM
 *DeviceState.receive_queue max_count:1

meshtastic/mesh.proto

@@ -1396,7 +1396,7 @@ message NeighborInfo {
   */
   uint32 node_id = 1;
   /*
-  * The node ID of the node sending info on its neighbors
+  * Field to pass neighbor info for the next sending cycle
   */
   uint32 last_sent_by_id = 2;
   /*