From 9ad1eee2f82967c0d1802acb7422d09f3a91d8af Mon Sep 17 00:00:00 2001
From: Niran Babalola <niran.babalola@coinbase.com>
Date: Wed, 11 Feb 2026 11:07:10 -0600
Subject: [PATCH] fix(gobrr): close rate limiter semaphore on shutdown

After shutdown, the replenisher stops adding permits but signers are
blocked forever in acquire_rate_permit().await. Call limiter.close() so
pending acquire_owned() calls return AcquireError, which the signer
already handles gracefully by breaking out of its loop.

Without this, all signers with target_tps configured deadlock on
shutdown, waiting for permits that will never come.
---
 crates/gobrr/src/runner.rs | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/crates/gobrr/src/runner.rs b/crates/gobrr/src/runner.rs
index cf72849..01a09e2 100644
--- a/crates/gobrr/src/runner.rs
+++ b/crates/gobrr/src/runner.rs
@@ -133,7 +133,13 @@ pub async fn start_load_test(config_path: &str) -> Result<LoadTestHandle> {
                 loop {
                     tokio::select! {
                         biased;
-                        _ = replenish_shutdown.recv() => break,
+                        _ = replenish_shutdown.recv() => {
+                            // Close the semaphore so signers blocked in
+                            // acquire_rate_permit() get an AcquireError
+                            // and can check their shutdown channel.
+                            limiter.close();
+                            break;
+                        }
                         _ = interval.tick() => {
                             let available = limiter.available_permits();
                             if available < max_permits {