From e2c0650d16d6d6de5c92f71cf4b1adf6f8d50027 Mon Sep 17 00:00:00 2001
From: Divma <divma@protonmail.com>
Date: Sun, 31 Oct 2021 22:30:19 +0000
Subject: [PATCH] Relax late sync committee penalty (#2752)

## Issue Addressed

Getting too many peers kicked due to slightly late sync committee messages as tested on.. under-performant hardware.

## Proposed Changes

Only penalize if the message is more than one slot late. Still ignore the message-

Co-authored-by: Divma <26765164+divagant-martian@users.noreply.github.com>
---
 .../beacon_processor/worker/gossip_methods.rs | 29 +++++++++++++++++--
 1 file changed, 27 insertions(+), 2 deletions(-)

diff --git a/beacon_node/network/src/beacon_processor/worker/gossip_methods.rs b/beacon_node/network/src/beacon_processor/worker/gossip_methods.rs
index fe6cb573a7..2e5ee5160b 100644
--- a/beacon_node/network/src/beacon_processor/worker/gossip_methods.rs
+++ b/beacon_node/network/src/beacon_processor/worker/gossip_methods.rs
@@ -1610,9 +1610,9 @@ impl<T: BeaconChainTypes> Worker<T> {
         metrics::register_sync_committee_error(&error);
 
         match &error {
-            SyncCommitteeError::FutureSlot { .. } | SyncCommitteeError::PastSlot { .. } => {
+            SyncCommitteeError::FutureSlot { .. } => {
                 /*
-                 * These errors can be triggered by a mismatch between our slot and the peer.
+                 * This error can be triggered by a mismatch between our slot and the peer.
                  *
                  *
                  * The peer has published an invalid consensus message, _only_ if we trust our own clock.
@@ -1631,6 +1631,31 @@ impl<T: BeaconChainTypes> Worker<T> {
                 // Do not propagate these messages.
                 self.propagate_validation_result(message_id, peer_id, MessageAcceptance::Ignore);
             }
+            SyncCommitteeError::PastSlot {
+                message_slot,
+                earliest_permissible_slot,
+            } => {
+                /*
+                 * This error can be triggered by a mismatch between our slot and the peer.
+                 *
+                 *
+                 * The peer has published an invalid consensus message, _only_ if we trust our own clock.
+                 */
+                trace!(
+                    self.log,
+                    "Sync committee message is not within the last MAXIMUM_GOSSIP_CLOCK_DISPARITY slots";
+                    "peer_id" => %peer_id,
+                    "type" => ?message_type,
+                );
+
+                // We tolerate messages that were just one slot late.
+                if *message_slot + 1 < *earliest_permissible_slot {
+                    self.gossip_penalize_peer(peer_id, PeerAction::HighToleranceError);
+                }
+
+                // Do not propagate these messages.
+                self.propagate_validation_result(message_id, peer_id, MessageAcceptance::Ignore);
+            }
             SyncCommitteeError::EmptyAggregationBitfield => {
                 /*
                  * The aggregate had no signatures and is therefore worthless.