From 40a026d92b26231a44fe3e0dd2315b25e303ba5e Mon Sep 17 00:00:00 2001
From: Fraser Hutchison <fraser@astria.org>
Date: Thu, 13 Feb 2025 11:13:09 +0000
Subject: [PATCH] increase mempool removal cache size

---
 crates/astria-sequencer/CHANGELOG.md       | 12 ++++++++++--
 crates/astria-sequencer/src/mempool/mod.rs | 16 +++++++++++++---
 2 files changed, 23 insertions(+), 5 deletions(-)

diff --git a/crates/astria-sequencer/CHANGELOG.md b/crates/astria-sequencer/CHANGELOG.md
index 80192e36f..80e6e54f2 100644
--- a/crates/astria-sequencer/CHANGELOG.md
+++ b/crates/astria-sequencer/CHANGELOG.md
@@ -9,6 +9,11 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+### Added
+
+- Add more thorough unit tests for all actions [#1916](https://github.com/astriaorg/astria/pull/1916).
+- Implement `BridgeTransfer` action [#1934](https://github.com/astriaorg/astria/pull/1934).
+
 ### Changed
 
 - Bump MSRV to 1.83.0 [#1857](https://github.com/astriaorg/astria/pull/1857).
@@ -19,8 +24,11 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - Remove events reporting on state storage creation [#1892](https://github.com/astriaorg/astria/pull/1892).
 - Use bridge address to determine asset in bridge unlock cost estimation instead
 of signer [#1905](https://github.com/astriaorg/astria/pull/1905).
-- Add more thorough unit tests for all actions [#1916](https://github.com/astriaorg/astria/pull/1916).
-- Implement `BridgeTransfer` action [#1934](https://github.com/astriaorg/astria/pull/1934).
+
+### Fixed
+
+- Increase mempool removal cache size to be greater than default CometBFT
+mempool size [#1969](https://github.com/astriaorg/astria/pull/1969).
 
 ## [1.0.0] - 2024-10-25
 
diff --git a/crates/astria-sequencer/src/mempool/mod.rs b/crates/astria-sequencer/src/mempool/mod.rs
index de71d097e..48fbf9529 100644
--- a/crates/astria-sequencer/src/mempool/mod.rs
+++ b/crates/astria-sequencer/src/mempool/mod.rs
@@ -29,6 +29,7 @@ use tokio::{
 use tracing::{
     error,
     instrument,
+    warn,
     Level,
 };
 pub(crate) use transactions_container::InsertionError;
@@ -58,7 +59,7 @@ const TX_TTL: Duration = Duration::from_secs(240);
 const MAX_PARKED_TXS_PER_ACCOUNT: usize = 15;
 /// Max number of transactions to keep in the removal cache. Should be larger than the max number of
 /// transactions allowed in the cometBFT mempool.
-const REMOVAL_CACHE_SIZE: usize = 4096;
+const REMOVAL_CACHE_SIZE: usize = 50_000;
 
 /// `RemovalCache` is used to signal to `CometBFT` that a
 /// transaction can be removed from the `CometBFT` mempool.
@@ -95,12 +96,21 @@ impl RemovalCache {
         };
 
         if self.remove_queue.len() == usize::from(self.max_size) {
-            // make space for the new transaction by removing the oldest transaction
+            // This should not happen if `REMOVAL_CACHE_SIZE` is >= CometBFT's configured mempool
+            // size.
+            //
+            // Make space for the new transaction by removing the oldest transaction.
             let removed_tx = self
                 .remove_queue
                 .pop_front()
                 .expect("cache should contain elements");
-            // remove transaction from cache if it is present
+            warn!(
+                tx_hash = %telemetry::display::hex(&removed_tx),
+                removal_cache_size = REMOVAL_CACHE_SIZE,
+                "popped transaction from appside mempool removal cache, CometBFT will not remove \
+                this transaction from its mempool - removal cache size possibly too low"
+            );
+            // Remove transaction from cache if it is present.
             self.cache.remove(&removed_tx);
         }
         self.remove_queue.push_back(tx_hash);