IDONTWANT message optimisation to cutoff for smaller messages (#6456)

* idontwant message opitmising

* requested changes and linter appeasing

* added the config cli flag

* Merge branch 'unstable' into fix/idontwant-optimise

* cli docs generated

* const declaration

* Hide extra technical cli flag

* passing ci

* Merge branch 'unstable' into fix/idontwant-optimise

beacon_node/lighthouse_network/src/config.rs

@@ -19,6 +19,7 @@ pub const DEFAULT_IPV4_ADDRESS: Ipv4Addr = Ipv4Addr::UNSPECIFIED;
 pub const DEFAULT_TCP_PORT: u16 = 9000u16;
 pub const DEFAULT_DISC_PORT: u16 = 9000u16;
 pub const DEFAULT_QUIC_PORT: u16 = 9001u16;
+pub const DEFAULT_IDONTWANT_MESSAGE_SIZE_THRESHOLD: usize = 1000usize;
 
 /// The maximum size of gossip messages.
 pub fn gossip_max_size(is_merge_enabled: bool, gossip_max_size: usize) -> usize {
@@ -141,6 +142,10 @@ pub struct Config {
 
     /// Configuration for the inbound rate limiter (requests received by this node).
     pub inbound_rate_limiter_config: Option<InboundRateLimiterConfig>,
+
+    /// Configuration for the minimum message size for which IDONTWANT messages are send in the mesh.
+    /// Lower the value reduces the optimization effect of the IDONTWANT messages.
+    pub idontwant_message_size_threshold: usize,
 }
 
 impl Config {
@@ -352,6 +357,7 @@ impl Default for Config {
             outbound_rate_limiter_config: None,
             invalid_block_storage: None,
             inbound_rate_limiter_config: None,
+            idontwant_message_size_threshold: DEFAULT_IDONTWANT_MESSAGE_SIZE_THRESHOLD,
         }
     }
 }
@@ -433,6 +439,7 @@ pub fn gossipsub_config(
     gossipsub_config_params: GossipsubConfigParams,
     seconds_per_slot: u64,
     slots_per_epoch: u64,
+    idontwant_message_size_threshold: usize,
 ) -> gossipsub::Config {
     fn prefix(
         prefix: [u8; 4],
@@ -498,6 +505,7 @@ pub fn gossipsub_config(
         .duplicate_cache_time(duplicate_cache_time)
         .message_id_fn(gossip_message_id)
         .allow_self_origin(true)
+        .idontwant_message_size_threshold(idontwant_message_size_threshold)
         .build()
         .expect("valid gossipsub configuration")
 }

beacon_node/lighthouse_network/src/service/mod.rs

@@ -237,6 +237,7 @@ impl<E: EthSpec> Network<E> {
             gossipsub_config_params,
             ctx.chain_spec.seconds_per_slot,
             E::slots_per_epoch(),
+            config.idontwant_message_size_threshold,
         );
 
         let score_settings = PeerScoreSettings::new(&ctx.chain_spec, gs_config.mesh_n());