From fb2ce909f66e0bbfa2d02bd34914008901f3275e Mon Sep 17 00:00:00 2001
From: Emilia Hane <emiliaha95@gmail.com>
Date: Sun, 15 Jan 2023 10:13:01 +0100
Subject: [PATCH] Avoid repeteadly updating blob info for multiple head
 candidates

---
 beacon_node/beacon_chain/src/beacon_chain.rs  | 28 ---------------
 .../beacon_chain/src/canonical_head.rs        | 35 ++++++++++++++++++-
 2 files changed, 34 insertions(+), 29 deletions(-)

diff --git a/beacon_node/beacon_chain/src/beacon_chain.rs b/beacon_node/beacon_chain/src/beacon_chain.rs
index b74f7309e2..250c64a1d3 100644
--- a/beacon_node/beacon_chain/src/beacon_chain.rs
+++ b/beacon_node/beacon_chain/src/beacon_chain.rs
@@ -50,7 +50,6 @@ use crate::persisted_fork_choice::PersistedForkChoice;
 use crate::pre_finalization_cache::PreFinalizationBlockCache;
 use crate::shuffling_cache::{BlockShufflingIds, ShufflingCache};
 use crate::snapshot_cache::{BlockProductionPreState, SnapshotCache};
-use crate::store::Split;
 use crate::sync_committee_verification::{
     Error as SyncCommitteeError, VerifiedSyncCommitteeMessage, VerifiedSyncContribution,
 };
@@ -3029,33 +3028,6 @@ impl<T: BeaconChainTypes> BeaconChain<T> {
             }
         }
 
-        if Some(current_epoch)
-            > self.spec.eip4844_fork_epoch.map(|eip4844_fork_epoch| {
-                eip4844_fork_epoch + *MIN_EPOCHS_FOR_BLOBS_SIDECARS_REQUESTS
-            })
-        {
-            let current_epoch_start_slot = current_epoch.start_slot(T::EthSpec::slots_per_epoch());
-
-            // Update db's metadata for blobs pruning.
-            if current_slot == current_epoch_start_slot {
-                if let Some(mut blob_info) = self.store.get_blob_info() {
-                    if let Some(data_availability_boundary) = self.data_availability_boundary() {
-                        let dab_slot =
-                            data_availability_boundary.end_slot(T::EthSpec::slots_per_epoch());
-                        if let Some(dab_state_root) = self.state_root_at_slot(dab_slot)? {
-                            blob_info.data_availability_boundary =
-                                Split::new(dab_slot, dab_state_root);
-
-                            self.store.compare_and_set_blob_info_with_write(
-                                self.store.get_blob_info(),
-                                Some(blob_info),
-                            )?;
-                        }
-                    }
-                }
-            }
-        }
-
         let txn_lock = self.store.hot_db.begin_rw_transaction();
 
         kv_store_ops.extend(self.store.convert_to_kv_batch(ops)?);
diff --git a/beacon_node/beacon_chain/src/canonical_head.rs b/beacon_node/beacon_chain/src/canonical_head.rs
index 83fe1940ad..1bd998261e 100644
--- a/beacon_node/beacon_chain/src/canonical_head.rs
+++ b/beacon_node/beacon_chain/src/canonical_head.rs
@@ -54,8 +54,9 @@ use slog::{crit, debug, error, warn, Logger};
 use slot_clock::SlotClock;
 use std::sync::Arc;
 use std::time::Duration;
-use store::{iter::StateRootsIterator, KeyValueStoreOp, StoreItem};
+use store::{iter::StateRootsIterator, KeyValueStoreOp, Split, StoreItem};
 use task_executor::{JoinHandle, ShutdownReason};
+use types::consts::eip4844::MIN_EPOCHS_FOR_BLOBS_SIDECARS_REQUESTS;
 use types::*;
 
 /// Simple wrapper around `RwLock` that uses private visibility to prevent any other modules from
@@ -794,8 +795,40 @@ impl<T: BeaconChainTypes> BeaconChain<T> {
             .is_optimistic_or_invalid();
 
         if self.store.get_config().prune_blobs {
+            let current_slot = self.slot()?;
+            let current_epoch = current_slot.epoch(T::EthSpec::slots_per_epoch());
+            if Some(current_epoch)
+                > self.spec.eip4844_fork_epoch.map(|eip4844_fork_epoch| {
+                    eip4844_fork_epoch + *MIN_EPOCHS_FOR_BLOBS_SIDECARS_REQUESTS
+                })
+            {
+                let current_epoch_start_slot =
+                    current_epoch.start_slot(T::EthSpec::slots_per_epoch());
+
+                // Update db's metadata for blobs pruning.
+                if current_slot == current_epoch_start_slot {
+                    if let Some(mut blob_info) = self.store.get_blob_info() {
+                        if let Some(data_availability_boundary) = self.data_availability_boundary()
+                        {
+                            let dab_slot =
+                                data_availability_boundary.end_slot(T::EthSpec::slots_per_epoch());
+                            if let Some(dab_state_root) = self.state_root_at_slot(dab_slot)? {
+                                blob_info.data_availability_boundary =
+                                    Split::new(dab_slot, dab_state_root);
+
+                                self.store.compare_and_set_blob_info_with_write(
+                                    self.store.get_blob_info(),
+                                    Some(blob_info),
+                                )?;
+                            }
+                        }
+                    }
+                }
+            }
+
             let store = self.store.clone();
             let log = self.log.clone();
+
             self.task_executor.spawn_blocking(
                 move || {
                     if let Err(e) = store.try_prune_blobs(false) {