From 7ff78ca082b2edf653188b10796ca817aa364cd9 Mon Sep 17 00:00:00 2001
From: Georgios Konstantopoulos <me@gakonst.com>
Date: Thu, 12 Feb 2026 12:07:52 -0500
Subject: [PATCH] perf(engine): use transaction count threshold for prewarm
 skip (#22094)

Co-authored-by: yk <yongkang@tempo.xyz>
Co-authored-by: Amp <amp@ampcode.com>
Co-authored-by: Ubuntu <ubuntu@dev-yk.tail388b2e.ts.net>
Co-authored-by: YK <chiayongkang@hotmail.com>
---
 crates/engine/tree/src/tree/payload_processor/mod.rs | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/crates/engine/tree/src/tree/payload_processor/mod.rs b/crates/engine/tree/src/tree/payload_processor/mod.rs
index b1ea7c7006..7c2b6af61f 100644
--- a/crates/engine/tree/src/tree/payload_processor/mod.rs
+++ b/crates/engine/tree/src/tree/payload_processor/mod.rs
@@ -94,6 +94,9 @@ pub const SPARSE_TRIE_MAX_NODES_SHRINK_CAPACITY: usize = 1_000_000;
 /// 144MB.
 pub const SPARSE_TRIE_MAX_VALUES_SHRINK_CAPACITY: usize = 1_000_000;
 
+/// Blocks with fewer transactions than this skip prewarming, since the fixed overhead of spawning
+/// prewarm workers exceeds the execution time saved.
+pub const SMALL_BLOCK_TX_THRESHOLD: usize = 5;
 /// Type alias for [`PayloadHandle`] returned by payload processor spawn methods.
 type IteratorPayloadHandle<Evm, I, N> = PayloadHandle<
     WithTxEnv<TxEnvFor<Evm>, <I as ExecutableTxIterator<Evm>>::Recovered>,
@@ -469,7 +472,8 @@ where
     where
         P: BlockReader + StateProviderFactory + StateReader + Clone + 'static,
     {
-        let skip_prewarm = self.disable_transaction_prewarming;
+        let skip_prewarm =
+            self.disable_transaction_prewarming || env.transaction_count < SMALL_BLOCK_TX_THRESHOLD;
 
         let saved_cache = self.disable_state_cache.not().then(|| self.cache_for(env.parent_hash));