[Perf] Add cache for most recent blocks

node/bft/ledger-service/Cargo.toml

@@ -18,7 +18,7 @@ edition = "2021"
 
 [features]
 default = [ ]
-ledger = [ "lru", "parking_lot", "rand", "tokio", "tracing" ]
+ledger = [ "lru", "parking_lot", "rand", "rayon", "tokio", "tracing" ]
 ledger-write = [ ]
 metrics = [ "dep:metrics", "snarkvm/metrics" ]
 mock = [ "parking_lot", "tracing" ]
@@ -52,6 +52,10 @@ optional = true
 version = "0.8"
 optional = true
 
+[dependencies.rayon]
+version = "1"
+optional = true
+
 [dependencies.snarkvm]
 workspace = true
 

node/bft/ledger-service/src/ledger.rs

@@ -23,13 +23,15 @@ use snarkvm::{
         puzzle::{Solution, SolutionID},
         store::ConsensusStorage,
     },
-    prelude::{Address, Field, FromBytes, Network, Result, bail},
+    prelude::{Address, Field, FromBytes, Network, Result, bail, cfg_into_iter},
 };
 
 use indexmap::IndexMap;
 use lru::LruCache;
 use parking_lot::{Mutex, RwLock};
+use rayon::prelude::*;
 use std::{
+    collections::BTreeMap,
     fmt,
     io::Read,
     ops::Range,
@@ -41,12 +43,15 @@ use std::{
 
 /// The capacity of the LRU holding the recently queried committees.
 const COMMITTEE_CACHE_SIZE: usize = 16;
+/// The capacity of the cache holding the highest blocks.
+const BLOCK_CACHE_SIZE: usize = 10;
 
 /// A core ledger service.
 #[allow(clippy::type_complexity)]
 pub struct CoreLedgerService<N: Network, C: ConsensusStorage<N>> {
     ledger: Ledger<N, C>,
     committee_cache: Arc<Mutex<LruCache<u64, Committee<N>>>>,
+    block_cache: Arc<RwLock<BTreeMap<u32, Block<N>>>>,
     latest_leader: Arc<RwLock<Option<(u64, Address<N>)>>>,
     shutdown: Arc<AtomicBool>,
 }
@@ -55,7 +60,8 @@ impl<N: Network, C: ConsensusStorage<N>> CoreLedgerService<N, C> {
     /// Initializes a new core ledger service.
     pub fn new(ledger: Ledger<N, C>, shutdown: Arc<AtomicBool>) -> Self {
         let committee_cache = Arc::new(Mutex::new(LruCache::new(COMMITTEE_CACHE_SIZE.try_into().unwrap())));
-        Self { ledger, committee_cache, latest_leader: Default::default(), shutdown }
+        let block_cache = Arc::new(RwLock::new(BTreeMap::new()));
+        Self { ledger, committee_cache, block_cache, latest_leader: Default::default(), shutdown }
     }
 }
 
@@ -120,13 +126,17 @@ impl<N: Network, C: ConsensusStorage<N>> LedgerService<N> for CoreLedgerService<
 
     /// Returns the block for the given block height.
     fn get_block(&self, height: u32) -> Result<Block<N>> {
-        self.ledger.get_block(height)
+        if let Some(block) = self.block_cache.read().get(&height) {
+            Ok(block.clone())
+        } else {
+            self.ledger.get_block(height)
+        }
     }
 
     /// Returns the blocks in the given block range.
     /// The range is inclusive of the start and exclusive of the end.
     fn get_blocks(&self, heights: Range<u32>) -> Result<Vec<Block<N>>> {
-        self.ledger.get_blocks(heights)
+        cfg_into_iter!(heights).map(|height| self.get_block(height)).collect()
     }
 
     /// Returns the solution for the given solution ID.
@@ -365,6 +375,12 @@ impl<N: Network, C: ConsensusStorage<N>> LedgerService<N> for CoreLedgerService<
         }
         // Advance to the next block.
         self.ledger.advance_to_next_block(block)?;
+        // Add the block to the block cache.
+        self.block_cache.write().insert(block.height(), block.clone());
+        // Prune the block cache if it exceeds the maximum size.
+        if self.block_cache.read().len() > BLOCK_CACHE_SIZE {
+            self.block_cache.write().pop_first();
+        }
         // Update BFT metrics.
         #[cfg(feature = "metrics")]
         {