diff --git a/gossip/src/duplicate_shred_handler.rs b/gossip/src/duplicate_shred_handler.rs
index a0cf0f0f0d..7789404b97 100644
--- a/gossip/src/duplicate_shred_handler.rs
+++ b/gossip/src/duplicate_shred_handler.rs
@@ -12,7 +12,7 @@ use {
     },
     std::{
         cmp::Reverse,
-        collections::{HashMap, HashSet},
+        collections::HashMap,
         sync::{Arc, RwLock},
     },
 };
@@ -34,7 +34,7 @@ pub struct DuplicateShredHandler {
     // together the chunks into the original proof before anything useful is done.
     buffer: HashMap<(Slot, Pubkey), BufferEntry>,
     // Slots for which a duplicate proof is already ingested.
-    consumed: HashSet<Slot>,
+    consumed: HashMap<Slot, bool>,
     // Cache last root to reduce read lock.
     last_root: Slot,
     blockstore: Arc<Blockstore>,
@@ -66,7 +66,7 @@ impl DuplicateShredHandler {
     ) -> Self {
         Self {
             buffer: HashMap::<(Slot, Pubkey), BufferEntry>::default(),
-            consumed: HashSet::<Slot>::default(),
+            consumed: HashMap::<Slot, bool>::default(),
             last_root: 0,
             cached_on_epoch: 0,
             cached_staked_nodes: Arc::new(HashMap::new()),
@@ -132,16 +132,15 @@ impl DuplicateShredHandler {
                     shred2.into_payload(),
                 )?;
             }
-            self.consumed.insert(slot);
+            self.consumed.insert(slot, true);
         }
         Ok(())
     }
 
-    fn should_consume_slot(&self, slot: Slot) -> bool {
+    fn should_consume_slot(&mut self, slot: Slot) -> bool {
         slot > self.last_root
             && slot < self.last_root.saturating_add(self.cached_slots_in_epoch)
-            && !self.consumed.contains(&slot)
-            && !self.blockstore.has_duplicate_shreds_in_slot(slot)
+            && should_consume_slot(slot, &self.blockstore, &mut self.consumed)
     }
 
     fn maybe_prune_buffer(&mut self) {
@@ -151,16 +150,18 @@ impl DuplicateShredHandler {
         if self.buffer.len() < BUFFER_CAPACITY.saturating_mul(2) {
             return;
         }
-        self.consumed.retain(|&slot| slot > self.last_root);
+        self.consumed.retain(|&slot, _| slot > self.last_root);
         // Filter out obsolete slots and limit number of entries per pubkey.
         {
             let mut counts = HashMap::<Pubkey, usize>::new();
             self.buffer.retain(|(slot, pubkey), _| {
-                *slot > self.last_root && !self.consumed.contains(slot) && {
-                    let count = counts.entry(*pubkey).or_default();
-                    *count = count.saturating_add(1);
-                    *count <= MAX_NUM_ENTRIES_PER_PUBKEY
-                }
+                *slot > self.last_root
+                    && should_consume_slot(*slot, &self.blockstore, &mut self.consumed)
+                    && {
+                        let count = counts.entry(*pubkey).or_default();
+                        *count = count.saturating_add(1);
+                        *count <= MAX_NUM_ENTRIES_PER_PUBKEY
+                    }
             });
         }
         if self.buffer.len() < BUFFER_CAPACITY {
@@ -181,34 +182,45 @@ impl DuplicateShredHandler {
             .collect();
         // Drop entries with lowest stake and rebuffer remaining ones.
         buffer.select_nth_unstable_by_key(BUFFER_CAPACITY, |&(stake, _)| Reverse(stake));
-        self.buffer = buffer
-            .into_iter()
-            .take(BUFFER_CAPACITY)
-            .map(|(_, entry)| entry)
-            .collect();
+        self.buffer.extend(
+            buffer
+                .into_iter()
+                .take(BUFFER_CAPACITY)
+                .map(|(_, entry)| entry),
+        );
     }
 }
 
+// Returns false if a duplicate proof is already ingested for the slot,
+// and updates local `consumed` cache with blockstore.
+fn should_consume_slot(
+    slot: Slot,
+    blockstore: &Blockstore,
+    consumed: &mut HashMap<Slot, bool>,
+) -> bool {
+    !*consumed
+        .entry(slot)
+        .or_insert_with(|| blockstore.has_duplicate_shreds_in_slot(slot))
+}
+
 #[cfg(test)]
 mod tests {
     use {
         super::*,
         crate::{
             cluster_info::DUPLICATE_SHRED_MAX_PAYLOAD_SIZE,
-            duplicate_shred::{from_shred, tests::new_rand_shred, DuplicateShred, Error},
-            duplicate_shred_listener::DuplicateShredHandlerTrait,
+            duplicate_shred::{from_shred, tests::new_rand_shred},
         },
         solana_ledger::{
             genesis_utils::{create_genesis_config_with_leader, GenesisConfigInfo},
             get_tmp_ledger_path_auto_delete,
             shred::Shredder,
         },
-        solana_runtime::{bank::Bank, bank_forks::BankForks},
+        solana_runtime::bank::Bank,
         solana_sdk::{
             signature::{Keypair, Signer},
             timing::timestamp,
         },
-        std::sync::Arc,
     };
 
     fn create_duplicate_proof(