From b5a44aeb3764265eb26b5c9794371710513f4875 Mon Sep 17 00:00:00 2001
From: int88 <106391185+int88@users.noreply.github.com>
Date: Thu, 27 Jul 2023 07:00:38 +0800
Subject: [PATCH] feat: metric of reorg depth of blockchain tree (#3860)

---
 crates/blockchain-tree/src/blockchain_tree.rs | 10 +++++++++-
 crates/blockchain-tree/src/metrics.rs         |  2 ++
 crates/storage/provider/src/chain.rs          |  5 +++++
 3 files changed, 16 insertions(+), 1 deletion(-)

diff --git a/crates/blockchain-tree/src/blockchain_tree.rs b/crates/blockchain-tree/src/blockchain_tree.rs
index ce92f48b2839..8edee773badf 100644
--- a/crates/blockchain-tree/src/blockchain_tree.rs
+++ b/crates/blockchain-tree/src/blockchain_tree.rs
@@ -1001,9 +1001,12 @@ impl<DB: Database, C: Consensus, EF: ExecutorFactory> BlockchainTree<DB, C, EF>
                     old: Arc::new(old_canon_chain.clone()),
                     new: Arc::new(new_canon_chain.clone()),
                 };
+                let reorg_depth = old_canon_chain.len();
+
                 // insert old canon chain
                 self.insert_chain(AppendableChain::new(old_canon_chain));
-                self.metrics.reorgs.increment(1);
+
+                self.update_reorg_metrics(reorg_depth as f64);
             } else {
                 // error here to confirm that we are reverting nothing from db.
                 error!(target: "blockchain_tree", "Reverting nothing from db on block: #{:?}", block_hash);
@@ -1094,6 +1097,11 @@ impl<DB: Database, C: Consensus, EF: ExecutorFactory> BlockchainTree<DB, C, EF>
         }
     }
 
+    fn update_reorg_metrics(&mut self, reorg_depth: f64) {
+        self.metrics.reorgs.increment(1);
+        self.metrics.latest_reorg_depth.set(reorg_depth);
+    }
+
     /// Update blockchain tree chains (canonical and sidechains) and sync metrics.
     ///
     /// NOTE: this method should not be called during the pipeline sync, because otherwise the sync
diff --git a/crates/blockchain-tree/src/metrics.rs b/crates/blockchain-tree/src/metrics.rs
index fd48307d4be2..b49ad3c5b921 100644
--- a/crates/blockchain-tree/src/metrics.rs
+++ b/crates/blockchain-tree/src/metrics.rs
@@ -13,6 +13,8 @@ pub struct TreeMetrics {
     pub canonical_chain_height: Gauge,
     /// The number of reorgs
     pub reorgs: Counter,
+    /// The latest reorg depth
+    pub latest_reorg_depth: Gauge,
     /// Longest sidechain height
     pub longest_sidechain_height: Gauge,
 }
diff --git a/crates/storage/provider/src/chain.rs b/crates/storage/provider/src/chain.rs
index b5d596c0164b..1633d360f065 100644
--- a/crates/storage/provider/src/chain.rs
+++ b/crates/storage/provider/src/chain.rs
@@ -136,6 +136,11 @@ impl Chain {
         Self { state, blocks: block_num_hash }
     }
 
+    /// Returns length of the chain.
+    pub fn len(&self) -> usize {
+        self.blocks.len()
+    }
+
     /// Get all receipts for the given block.
     pub fn receipts_by_block_hash(&self, block_hash: BlockHash) -> Option<&[Receipt]> {
         let num = self.block_number(block_hash)?;