From 1b303c4e139a6e5a980871c9252e707926aba56d Mon Sep 17 00:00:00 2001
From: Victor Allombert <victor.allombert@nomadic-labs.com>
Date: Thu, 22 Feb 2024 11:23:24 +0100
Subject: [PATCH 1/2] Shell: avoid head validation request on blocks know as
 current head

---
 src/lib_shell/chain_validator.ml | 23 ++++++++++++++++++-----
 1 file changed, 18 insertions(+), 5 deletions(-)

diff --git a/src/lib_shell/chain_validator.ml b/src/lib_shell/chain_validator.ml
index 86ff747dc511..e55f63ea2a1e 100644
--- a/src/lib_shell/chain_validator.ml
+++ b/src/lib_shell/chain_validator.ml
@@ -556,14 +556,27 @@ let on_notify_branch w peer_id locator =
       Peer_validator.notify_branch pv locator ;
       return_ok_unit)
 
-let on_notify_head w peer_id (hash, header) mempool =
+let on_notify_head w peer_id (block_hash, header) mempool =
   let open Lwt_syntax in
   let nv = Worker.state w in
-  let* () = check_and_update_synchronisation_state w (hash, header) peer_id in
+  let* () =
+    check_and_update_synchronisation_state w (block_hash, header) peer_id
+  in
+  let* current_head = Store.Chain.current_head nv.parameters.chain_store in
   let* (r : (_, Empty.t) result) =
-    with_activated_peer_validator w peer_id (fun pv ->
-        Peer_validator.notify_head pv hash header ;
-        return_ok_unit)
+    (* To minimize unnecessary calls to notify_head, we do nothing
+       when the received block is actually the current head or it's
+       predecessor. *)
+    if
+      not
+        Block_hash.(
+          Store.Block.hash current_head = block_hash
+          || Store.Block.predecessor current_head = block_hash)
+    then
+      with_activated_peer_validator w peer_id (fun pv ->
+          Peer_validator.notify_head pv block_hash header ;
+          return_ok_unit)
+    else return_ok_unit
   in
   match r with
   | Ok () -> (
-- 
GitLab


From a4685f3f15958cd5202fd57120fdeda598328a43 Mon Sep 17 00:00:00 2001
From: Victor Allombert <victor.allombert@nomadic-labs.com>
Date: Thu, 22 Feb 2024 14:08:45 +0100
Subject: [PATCH 2/2] Store: improve Store.Block.is_known_valid

---
 src/lib_store/unix/store.ml | 12 +++++++++---
 1 file changed, 9 insertions(+), 3 deletions(-)

diff --git a/src/lib_store/unix/store.ml b/src/lib_store/unix/store.ml
index 56406783ab54..84f66f04c5e2 100644
--- a/src/lib_store/unix/store.ml
+++ b/src/lib_store/unix/store.ml
@@ -252,12 +252,18 @@ module Block = struct
 
   (* I/O operations *)
 
-  let is_known_valid chain_store hash =
+  let is_known_valid chain_store block_hash =
     let open Lwt_syntax in
     let* current_head = current_head chain_store in
-    if Block_repr.hash current_head = hash then return_true
+    if
+      Block_hash.(
+        Block_repr.hash current_head = block_hash
+        || Block_repr.predecessor current_head = block_hash)
+    then return_true
     else
-      let* r = Block_store.(mem chain_store.block_store (Block (hash, 0))) in
+      let* r =
+        Block_store.(mem chain_store.block_store (Block (block_hash, 0)))
+      in
       match r with
       | Ok k -> return k
       | Error _ ->
-- 
GitLab