diff --git a/src/accounts.rs b/src/accounts.rs
index 9537019305b36f..71f0707db88743 100644
--- a/src/accounts.rs
+++ b/src/accounts.rs
@@ -337,7 +337,7 @@ impl Accounts {
     }
     /// accounts starts with an empty data structure for every fork
     /// self is trunk, merge the fork into self
-    pub fn merge_into_trunk(&mut self, other: Self) {
+    pub fn merge_into_trunk(&self, other: Self) {
         assert!(other.account_locks.lock().unwrap().is_empty());
         let db = other.accounts_db.into_inner().unwrap();
         let mut mydb = self.accounts_db.write().unwrap();
diff --git a/src/bank.rs b/src/bank.rs
index 856dab7a748ba9..3e03ac2ee73e83 100644
--- a/src/bank.rs
+++ b/src/bank.rs
@@ -313,16 +313,6 @@ impl Bank {
         self.forks.read().unwrap().trunk_fork()
     }
 
-    #[must_use]
-    fn process_and_record_transactions_on_fork(
-        &self,
-        fork: u64,
-        txs: &[Transaction],
-        poh: Option<&PohRecorder>,
-    ) -> Result<(Vec<Result<()>>)> {
-        let state = self.forks.read().unwrap().bank_state(fork);
-        state.process_and_record_transactions(Some(&self.subscriptions), txs, poh)
-    }
     #[must_use]
     pub fn process_and_record_transactions(
         &self,
diff --git a/src/bank_state.rs b/src/bank_state.rs
index f3fe05a036465b..d7e95025acf587 100644
--- a/src/bank_state.rs
+++ b/src/bank_state.rs
@@ -31,12 +31,12 @@ pub struct BankCheckpoint {
     /// status cache
     status_cache: RwLock<StatusCache>,
     finalized: AtomicBool,
-    pub fork_id: u64,
+    fork_id: AtomicUsize,
 }
 
 impl std::fmt::Debug for BankCheckpoint {
     fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
-        write!(f, "BankCheckpoint {{ fork_id: {} }}", self.fork_id)
+        write!(f, "BankCheckpoint {{ fork_id: {} }}", self.fork_id())
     }
 }
 
@@ -48,7 +48,7 @@ impl BankCheckpoint {
             entry_q: RwLock::new(EntryQueue::default()),
             status_cache: RwLock::new(StatusCache::new(last_id)),
             finalized: AtomicBool::new(false),
-            fork_id,
+            fork_id: AtomicUsize::new(fork_id as usize),
         }
     }
     /// Create an Bank using a deposit.
@@ -189,6 +189,9 @@ impl BankCheckpoint {
         self.accounts.hash_internal_state()
     }
 
+    pub fn fork_id(&self) -> u64 {
+        self.fork_id.load(Ordering::Relaxed) as u64
+    }
     /// create a new fork for the bank state
     pub fn fork(&self, fork_id: u64, last_id: &Hash) -> Self {
         Self {
@@ -196,12 +199,12 @@ impl BankCheckpoint {
             entry_q: RwLock::new(self.entry_q.read().unwrap().fork()),
             status_cache: RwLock::new(StatusCache::new(last_id)),
             finalized: AtomicBool::new(false),
-            fork_id,
+            fork_id: AtomicUsize::new(fork_id as usize),
         }
     }
     /// consume the checkpoint into the trunk state
     /// self becomes the new trunk and its fork_id is updated
-    pub fn merge_into_trunk(&mut self, other: Self) {
+    pub fn merge_into_trunk(&self, other: Self) {
         let (accounts, entry_q, status_cache, fork_id) = {
             (
                 other.accounts,
@@ -219,7 +222,8 @@ impl BankCheckpoint {
             .write()
             .unwrap()
             .merge_into_trunk(status_cache.into_inner().unwrap());
-        self.fork_id = fork_id;
+        self.fork_id
+            .store(fork_id.load(Ordering::Relaxed), Ordering::Relaxed);
     }
 }
 
@@ -265,7 +269,7 @@ impl BankState {
         mut results: Vec<Result<()>>,
         error_counters: &mut ErrorCounters,
     ) -> Vec<Result<()>> {
-        for c in self.checkpoints {
+        for c in &self.checkpoints {
             let status_cache = c.status_cache.read().unwrap();
             for (i, tx) in txs.iter().enumerate() {
                 if results[i] == Ok(()) && status_cache.has_signature(&tx.signatures[0]) {
@@ -489,7 +493,7 @@ impl BankState {
                 //TODO: this sanity check needs to be fixed once forks contain the PoH ticks that
                 //connect them to the previous fork.  We need a way to identify the fork from the
                 //entry itself, or have that information passed through.
-                assert_eq!(e.tick_height / BLOCK_TICK_COUNT, head.fork_id);
+                assert_eq!(e.tick_height / BLOCK_TICK_COUNT, head.fork_id());
                 let results = self.execute_and_commit_transactions(
                     None,
                     &e.transactions,
@@ -543,8 +547,8 @@ impl BankState {
             let finish = entries.last().unwrap().tick_height;
             // Fork sanity check
             //TODO: same as the other fork sanity check
-            assert_eq!(finish / BLOCK_TICK_COUNT, head.fork_id);
-            if (finish + 1) / BLOCK_TICK_COUNT != head.fork_id {
+            assert_eq!(finish / BLOCK_TICK_COUNT, head.fork_id());
+            if (finish + 1) / BLOCK_TICK_COUNT != head.fork_id() {
                 head.finalize();
             }
         }
@@ -580,7 +584,7 @@ impl BankState {
         Ok(())
     }
     pub fn get_signature_status(&self, signature: &Signature) -> Option<Result<()>> {
-        for c in self.checkpoints {
+        for c in &self.checkpoints {
             if let Some(status) = c.get_signature_status(signature) {
                 return Some(status);
             }
@@ -588,7 +592,7 @@ impl BankState {
         None
     }
     pub fn has_signature(&self, signature: &Signature) -> bool {
-        for c in self.checkpoints {
+        for c in &self.checkpoints {
             if c.has_signature(signature) {
                 return true;
             }
@@ -623,7 +627,7 @@ mod test {
     }
 
     fn new_state(mint: &Keypair, tokens: u64, last_id: &Hash) -> BankState {
-        let accounts = [(mint.pubkey(), Account::new(3, 0, Pubkey::default()))];
+        let accounts = [(mint.pubkey(), Account::new(tokens, 0, Pubkey::default()))];
         let bank = Arc::new(BankCheckpoint::new_from_accounts(0, &accounts, &last_id));
         BankState {
             checkpoints: vec![bank],
@@ -636,7 +640,6 @@ mod test {
         let mint = Keypair::new();
         let alice = Keypair::new();
         let bob = Keypair::new();
-        let accounts = [(mint.pubkey(), Account::new(3, 0, Pubkey::default()))];
         let bank = new_state(&mint, 3, &last_id);
 
         let tx1 = Transaction::system_new(&mint, alice.pubkey(), 1, last_id);
diff --git a/src/checkpoints.rs b/src/checkpoints.rs
index da6dabb6d3e66b..7d04fa4b75a763 100644
--- a/src/checkpoints.rs
+++ b/src/checkpoints.rs
@@ -15,7 +15,7 @@ pub struct Checkpoints<T> {
     pub latest: HashSet<u64>,
 }
 
-impl<T> Checkpoints<T> {
+impl<T: Clone> Checkpoints<T> {
     pub fn is_empty(&self) -> bool {
         self.checkpoints.is_empty()
     }
@@ -68,11 +68,12 @@ impl<T> Checkpoints<T> {
                 break;
             }
             let trunk = queue.pop_front().unwrap();
-            let new_data = self.load(trunk).expect("load from inverse").clone();
-            new.store(trunk, new_data.0, new_data.1);
-            let children = inverse.get(&trunk).unwrap_or(&HashSet::new());
-            let mut next = children.into_iter().map(|x| *x).collect();
-            queue.append(&mut next);
+            let (data, prev) = self.load(trunk).expect("load from inverse").clone();
+            new.store(trunk, data.clone(), prev);
+            if let Some(children) = inverse.get(&trunk) {
+                let mut next = children.into_iter().map(|x| *x).collect();
+                queue.append(&mut next);
+            }
         }
         new
     }
diff --git a/src/forks.rs b/src/forks.rs
index c5ea29acbb92ea..5d9f7d06032d4b 100644
--- a/src/forks.rs
+++ b/src/forks.rs
@@ -61,11 +61,11 @@ impl Forks {
             let len = states.len();
             let old_trunk = states[len - 1].clone();
             let merged = states[len - 2].clone();
-            (old_trunk.1, merged.1, merged.0)
+            (old_trunk.1.clone(), merged.1.clone(), merged.0)
         };
         let idag = self.checkpoints.invert();
         let new_checkpoints = self.checkpoints.prune(new_trunk_id, &idag);
-        let old_id = old.fork_id;
+        let old_id = old.fork_id();
         self.checkpoints = new_checkpoints;
         self.trunk_fork = new_trunk_id;
         // old should have been pruned
@@ -80,17 +80,17 @@ impl Forks {
         // merge all the new changes into the old instance under the new id
         // this should consume `new`
         // new should have no other references
-        let new: BankCheckpoint = Arc::try_unwrap(*new).unwrap();
+        let new: BankCheckpoint = Arc::try_unwrap(new).unwrap();
         old.merge_into_trunk(new);
-        assert_eq!(old.fork_id, new_trunk_id);
+        assert_eq!(old.fork_id(), new_trunk_id);
         Ok(new_trunk_id)
     }
 
     /// Initialize the first trunk
     pub fn init_trunk_fork(&mut self, checkpoint: BankCheckpoint) {
         assert!(self.checkpoints.is_empty());
-        self.live_fork = checkpoint.fork_id;
-        self.trunk_fork = checkpoint.fork_id;
+        self.live_fork = checkpoint.fork_id();
+        self.trunk_fork = checkpoint.fork_id();
         //TODO: using u64::MAX as the impossible checkpoint
         //this should be a None instead
         self.checkpoints
diff --git a/src/replay_stage.rs b/src/replay_stage.rs
index 3154036d9fe818..0c143c25a62ecd 100644
--- a/src/replay_stage.rs
+++ b/src/replay_stage.rs
@@ -74,7 +74,7 @@ impl ReplayStage {
             if blocks.last().unwrap().1 != current {
                 blocks.push((vec![], current, prev));
             }
-            blocks.last().unwrap().0.push(e);
+            blocks.last_mut().unwrap().0.push(e);
         }
         blocks
     }
@@ -87,8 +87,8 @@ impl ReplayStage {
         _keypair: &Arc<Keypair>,
         _vote_account_keypair: &Arc<Keypair>,
         _vote_blob_sender: Option<&BlobSender>,
-        ledger_entry_sender: &EntrySender,
-        entry_height: &mut u64,
+        _ledger_entry_sender: &EntrySender,
+        _entry_height: &mut u64,
         last_entry_id: &mut Hash,
     ) -> Result<()> {
         let timer = Duration::new(1, 0);
@@ -139,8 +139,8 @@ impl ReplayStage {
         let now = Instant::now();
         // TODO: make this work
         // let options = vec![];
-        // for c in bank.checkpoints.live {
-        //     let state = bank.collect(c);
+        // for c in bank.live_forks() {
+        //     let state = bank.bank_state(c);
         //     if is_valid_vote(state.entry_height()) {
         //         options.push(state);
         //     }