From 0409b3f45fd65f89885d9be6bf048b16416fb70d Mon Sep 17 00:00:00 2001
From: Pierre Massat <pierre.massat@sentry.io>
Date: Thu, 4 Jan 2024 10:40:50 -0500
Subject: [PATCH] ref(rust): Do not do extra work when merging if not needed
 (#5294)

---
 .../rust_arroyo/src/processing/strategies/reduce.rs       | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/rust_snuba/rust_arroyo/src/processing/strategies/reduce.rs b/rust_snuba/rust_arroyo/src/processing/strategies/reduce.rs
index b3d662087e..f6d014c8eb 100644
--- a/rust_snuba/rust_arroyo/src/processing/strategies/reduce.rs
+++ b/rust_snuba/rust_arroyo/src/processing/strategies/reduce.rs
@@ -43,8 +43,12 @@ impl<T, TResult> BatchState<T, TResult> {
 
         let tmp = self.value.take().unwrap();
         let payload = message.into_payload();
-        self.message_count += (self.compute_batch_size)(&payload);
-        self.value = Some((self.accumulator)(tmp, payload));
+        let batch_size = (self.compute_batch_size)(&payload);
+
+        if batch_size > 0 {
+            self.message_count += batch_size;
+            self.value = Some((self.accumulator)(tmp, payload));
+        }
     }
 }